The posterior pituitary stores and secretes (but does not synthesize) the following important endocrine hormones: Magnocellular neurons:
Posterior
Pituitary gland
Pituitary gland | Posterior
It store and secretes (but does not synthesize) the important endocrine hormones. It stores and secretes (but does not synthesize) Sorry. I cannot find the answer based on the context. Sorry. I cannot find the answer based on the context.
hypothalamic amenorrhea will result in the increased secretion of thyroid stimulating hormone (tsh)
user
Sorry. I cannot find the answer based on the context.
assistant
what is hypopituitarism?
user
A decreased ("hypo") secretion of one or more of the eight hormones normally produced by the pituitary gland at the base of the brain.
assistant
what are the indications of it?
user
Insufficiency of follicle-stimulating hormone (FSH) and/or luteinizing hormone (LH) leading to sex hormone abnormalities. Growth hormone deficiency is more common in people with an underlying tumor than those with other causes.
assistant
how this can be treated?
user
Removing the underlying cause, treating the hormone deficiencies, and addressing any other repercussions that arise from the hormone deficiencies.
assistant
you mentioned a gland above, where is it located in human body?
user
The bottom of the hypothalamus at the base of the brain.
assistant
what is the size of this gland?
user
The size of a pea
assistant
what is the functions of anterior lobe of this gland?
user
Synthesizes and secretes hormones; regulates several physiological processes including stress, growth, reproduction, and lactation.
assistant
which hormones are synthesized by this lobe?
user
Growth hormone, follicle-stimulating hormone (FSH) and luteinizing hormone (LH), thyroid stimulating hormone (TSH) etc
assistant
how is the posterior lobe different from the anterior lobe?
user
In general, the intermediate lobe tends to be well developed, and may equal the remainder of the anterior pituitary in size. The posterior lobe typically forms a sheet of tissue at the base of the pituitary stalk, and in most cases sends irregular finger-like projection into the tissue of the anterior pituitary, which lies directly beneath it. The anterior pituitary is typically divided into two regions, a more anterior "rostral" portion and a posterior "proximal" portion, but the boundary between the two is often not clearly marked. In elasmobranchs there is an additional, "ventral lobe" beneath the anterior pituitary proper.
Pituitary gland | Other animals
The pituitary gland is divided into two lobes, the anterior lobe (which accounts for two thirds of the volume of the gland), and the posterior lobe (one third of the volume) separated by the pars intermedia. The posterior lobe (the neural lobe or neurohypophysis) of the pituitary gland is not, despite its name, a true gland. The posterior lobe contains axons of neurons that extend from the hypothalamus to which it is connected via the pituitary stalk. The hormones vasopressin and oxytocin, produced by the neurons of the supraoptic and paraventricular nuclei of the hypothalamus, are stored in the posterior lobe and released from axon endings (dendrites) within the lobe.
Pituitary adenoma | Mechanism
The posterior pituitary (or neurohypophysis) is the posterior lobe of the pituitary gland which is part of the endocrine system. The posterior pituitary is not glandular as is the anterior pituitary. Instead, it is largely a collection of axonal projections from the hypothalamus that terminate behind the anterior pituitary, and serve as a site for the secretion of neurohypophysial hormones (oxytocin and vasopressin) directly into the blood. The hypothalamic–neurohypophyseal system is composed of the hypothalamus (the paraventricular nucleus and supraoptic nucleus), posterior pituitary, and these axonal projections.
Posterior pituitary | Introduction
In response to the releasing hormone rate, the anterior pituitary produces its hormones (TSH, ACTH, LH, FSH, GH) which in turn stimulate effector hormone glands in the body, while prolactin (PRL) acts directly on the breast gland. Once the effector glands produce sufficient hormones (thyroxine, cortisol, estradiol or testosterone and IGF-1), both the hypothalamus and the pituitary cells sense their abundance and reduce their secretion of stimulating hormones. The hormones of the posterior pituitary are produced in the hypothalamus and are carried by nerve endings to the posterior lobe; their feedback system is therefore located in the hypothalamus, but damage to the nerve endings would still lead to a deficiency in hormone release.
Hypopituitarism | Pathophysiology
The pituitary gland secretes hormones that directly impact the body as well as hormones that indirectly control body functions because they activate other endocrine glands, such as the adrenal cortex (ACTH) and the thyroid gland (TSH). These two glands when stimulated by pituitary hormones then release their own hormones. The pituitary gland has two lobes, the anterior lobe and the posterior lobe. The anterior lobe secretes: growth hormone (GH), Luteinizing hormone (LH), Follicle stimulating hormone (FSH), Adrenocorticotropic hormone (ACTH), Thyroid-stimulating hormone (TSH), Prolactin (PRL), and the posterior lobe secretes: Antidieuretic hormone (ADH), and Oxytocin. There is an intermediate lobe, in adult humans it is just a thin layer of cells between the anterior and posterior pituitary, nearly indistinguishable from the anterior lobe.
Head and neck anatomy | Endocrine glands
The pituitary gland sits in a protective bony enclosure called the sella turcica ("Turkish chair/saddle"). It is composed of three lobes: the anterior, intermediate, and posterior lobes. In many animals, these lobes are distinct. However, in humans, the intermediate lobe is but a few cell layers thick and indistinct; as a result, it is often considered part of the anterior pituitary. In all animals, the fleshy, glandular anterior pituitary is distinct from the neural composition of the posterior pituitary. The anterior pituitary is composed of three regions: Nota bene: The terms "basophil" and "acidophil" are used by some books, whereas others prefer not to use these terms.
Anterior pituitary | Structure
The pituitary gland, in humans, is a pea-sized gland that sits in a protective bony enclosure called the sella turcica. It is composed of two lobes: anterior and posterior, with the intermediate lobe that joins the two regions. In many animals, these three lobes are distinct. The intermediate is avascular and almost absent in human beings. The intermediate lobe is present in many animal species, in particular in rodents, mice and rats, that have been used extensively to study pituitary development and function. In all animals, the fleshy, glandular anterior pituitary is distinct from the neural composition of the posterior pituitary, which is an extension of the hypothalamus.
Pituitary gland | Structure
The posterior pituitary (or neurohypophysis) is a lobe of the gland that is functionally connected to the hypothalamus by the median eminence via a small tube called the pituitary stalk (also called the infundibular stalk or the infundibulum). Hormones secreted from the pituitary gland help to control growth, blood pressure, energy management, all functions of the sex organs, thyroid glands and metabolism as well as some aspects of pregnancy, childbirth, breastfeeding, water/salt concentration at the kidneys, temperature regulation and pain relief.
Pituitary gland | Introduction
Although rudimentary in humans (and often considered part of the anterior pituitary), the intermediate lobe located between the anterior and posterior pituitary is important to many animals. For instance, in fish, it is believed to control physiological color change. In adult humans, it is just a thin layer of cells between the anterior and posterior pituitary. The intermediate lobe produces melanocyte-stimulating hormone (MSH), although this function is often (imprecisely) attributed to the anterior pituitary. The intermediate lobe is, in general, not well developed in tetrapods, and is entirely absent in birds.
Pituitary gland | Intermediate lobe
The posterior pituitary lobe is formed from the diverticulum. Portions of the pituitary tissue may remain in the nasopharyngeal midline. In rare cases this results in functioning ectopic hormone-secreting tumors in the nasopharynx. The functional development of the anterior pituitary involves spatiotemporal regulation of transcription factors expressed in pituitary stem cells and dynamic gradients of local soluble factors. The coordination of the dorsal gradient of pituitary morphogenesis is dependent on neuroectodermal signals from the infundibular bone morphogenetic protein 4 (BMP4). This protein is responsible for the development of the initial invagination of the Rathke’s pouch. Other essential proteins necessary for pituitary cell proliferation are Fibroblast growth factor 8 (FGF8), Wnt4, and Wnt5.
Development of the endocrine system | Pituitary gland
This is due to the possible confusion with white blood cells, where one may also find basophils and acidophils.
Anterior pituitary | Structure
Two hormones are classically considered as being related to the posterior pituitary: oxytocin and vasopressin. These hormones are created in the hypothalamus and released in the posterior pituitary. After creation, they are stored in neurosecretory vesicles regrouped into Herring bodies before being secreted in the posterior pituitary via the bloodstream.
Posterior pituitary | Hormone secretion
Oxytocin and anti-diuretic hormone are not secreted in the posterior lobe, merely stored.
List of human endocrine organs and actions | <a href="Posterior%20pituitary">Posterior pituitary</a> lobe (neurohypophysis)
The posterior pituitary stores and secretes (but does not synthesize) the following important endocrine hormones: Magnocellular neurons:
Pituitary gland | Posterior
Other sources specifically exclude it from the pituitary.
Posterior pituitary | Structure
The anterior pituitary synthesizes and secretes hormones. All releasing hormones (-RH) referred to, can also be referred to as releasing factors (-RF). Somatotropes: Corticotropes:
Pituitary gland | Anterior
A major organ of the endocrine system, the anterior pituitary (also called the adenohypophysis or pars anterior) is the glandular, anterior lobe that together with the posterior lobe (posterior pituitary, or the neurohypophysis) makes up the pituitary gland (hypophysis). The anterior pituitary regulates several physiological processes, including stress, growth, reproduction, and lactation. Proper functioning of the anterior pituitary and of the organs it regulates can often be ascertained via blood tests that measure hormone levels.
Anterior pituitary | Introduction
The pituitary gland is located at the base of the brain, and intimately connected with the hypothalamus. It consists of two lobes: the posterior pituitary, which consists of nervous tissue branching out of the hypothalamus, and the anterior pituitary, which consists of hormone-producing epithelium. The posterior pituitary secretes antidiuretic hormone, which regulates osmolarity of the blood, and oxytocin, which causes contractions of the uterus in childbirth and participates in breastfeeding. The pituitary develops in the third week of embryogenesis from interactions between the diencephalon part of the brain and the nasal cavity. The brain cells secrete FGF-8, Wnt5a and BMP-4, and the oral cavity BMP-2.
Hypopituitarism | Pathophysiology
The pituitary gland is divided into two sections: the anterior pituitary and the posterior pituitary. The hypothalamus controls the anterior pituitary's hormone secretion by sending trophic hormones down the hypothalamohypophysial portal system. For example, thyrotropin-releasing hormone stimulates the secretion of thyroid-stimulating hormone by the anterior pituitary. The posterior pituitary is innervated by the hypothalamus; the hormones oxytocin and vasopressin are synthesized by neuroendocrine cells in the hypothalamus and stored at the nerves' ends in the posterior pituitary. They are secreted directly into systemic circulation by the hypothalamic neurons.
Neuroendocrinology | Pituitary gland
The pituitary gland is subdivided into two lobes, the anterior pituitary and the posterior pituitary (also known as the adenohypophysis and neurohypophysis respectively). Each one functions as a separate endocrine organ, and both are circumventricular organs. The anterior pituitary contains non-neural secretory cells derived from oral ectoderm which are indirectly controlled by "releasing hormones" from the median eminence of the hypothalamus, through the hypophyseal portal circulation. The posterior pituitary consists of axonal projections that directly extend from cell bodies in the hypothalamus, through the infundibulum. It is located in the sella turcica of the sphenoid bone at the base of the skull.
Circumventricular organs | Anatomy
In vertebrate anatomy, the pituitary gland, or hypophysis, is an endocrine gland, about the size of a pea and weighing in humans. It is a protrusion off the bottom of the hypothalamus at the base of the brain. The hypophysis rests upon the hypophysial fossa of the sphenoid bone in the center of the middle cranial fossa and is surrounded by a small bony cavity (sella turcica) covered by a dural fold (diaphragma sellae). The anterior pituitary (or adenohypophysis) is a lobe of the gland that regulates several physiological processes (including stress, growth, reproduction, and lactation). The intermediate lobe synthesizes and secretes melanocyte-stimulating hormone.
Pituitary gland | Introduction
The pituitary gland is found in all vertebrates, but its structure varies among different groups. The division of the pituitary described above is typical of mammals, and is also true, to varying degrees, of all tetrapods. However, only in mammals does the posterior pituitary have a compact shape. In lungfish, it is a relatively flat sheet of tissue lying above the anterior pituitary, but in amphibians, reptiles, and birds, it becomes increasingly well developed. The intermediate lobe is, in general, not well developed in any species and is entirely absent in birds. The structure of the pituitary in fish, apart from the lungfish, is generally different from that in other animals.
Pituitary gland | Other animals
The posterior pituitary consists mainly of neuronal projections (axons) of magnocellular neurosecretory cells extending from the supraoptic and paraventricular nuclei of the hypothalamus. These axons store and release neurohypophysial hormones oxytocin and vasopressin into the neurohypophyseal capillaries, from there they get into the systemic circulation (and partly back into the hypophyseal portal system). In addition to axons, the posterior pituitary also contains pituicytes, specialized glial cells resembling astrocytes assisting in the storage and release of the hormones. Classification of the posterior pituitary varies, but most sources include the two regions below: The median eminence is only occasionally included as part of the posterior pituitary.
Posterior pituitary | Structure
The intermediate lobe synthesizes and secretes the following important endocrine hormone:
Pituitary gland | Intermediate
The anterior pituitary is derived from the ectoderm, more specifically from that of Rathke’s pouch, part of the developing hard palate in the embryo. The pouch eventually loses its connection with the pharynx, giving rise to the anterior pituitary. The anterior wall of Rathke's pouch proliferates, filling most of the pouch to form the pars distalis and the pars tuberalis. The posterior wall of the anterior pituitary forms the pars intermedia. Its formation from the soft tissues of the upper palate contrasts with the posterior pituitary, which originates from neuroectoderm.
Anterior pituitary | Development
These hypophysiotropic hormones stimulate or inhibit the release of hormones from the anterior pituitary. Further, anatomical evidence exists for bidirectional communication between the median eminence and the arcuate and ventromedial nucleus of the hypothalamus.
Median eminence | Physiology
Three hormones (usually synthetic analogues) are injected as a bolus into the patient's vein to stimulate the anterior pituitary gland: The gland's response is assessed by measuring the rise in cortisol and growth hormone (GH) in response to the hypoglycaemia caused by insulin, rises in prolactin and thyroid-stimulating hormone (TSH) caused by TRH and rises in luteinizing hormone (LH) and follicle-stimulating hormone (FSH) caused by GnRH. Blood glucose levels are also monitored to ensure appropriate levels of hypoglycemia are achieved.
Combined rapid anterior pituitary evaluation panel | Process
It is impossible to determine accurate location of the central or precentral sulci from an endocast. Still it can provide a rough idea of lobe sizes.
Paleoneurobiology | Relative lobe size
The furrow that usually separates the anterior and posterior glabella (F3) is effaced. The lateral furrows of the posterior glabella (F2) are weakly impressed. The node on the glabella is located near its anterior margin. The pygidial axis is very short, and tapers to the back. The posterior lobe is transverse trapeziform, and carries an indistinct median ridge, and behind which the axial furrow deepens.
Galbagnostus | Description
Tropic hormones from the anterior pituitary include:
Tropic hormone | Anterior pituitary
Unlike tumors of the posterior Pituitary, Pituitary adenomas are classified as endocrine tumors (not brain tumors). Pituitary adenomas are classified based upon anatomical, histological and functional criteria.
Pituitary adenoma | Classification
The intermediate lobe produces melanocyte-stimulating hormone (MSH).
Head and neck anatomy | Endocrine glands
As men age, the enzymes aromatase and 5-alpha reductase increase in activity. These enzymes are responsible for converting androgen hormones into estrogen and dihydrotestosterone, respectively. This metabolism of androgen hormones leads to a decrease in testosterone but increased levels of DHT and estrogen. Both the glandular epithelial cells and the stromal cells (including muscular fibers) undergo hyperplasia in BPH. Most sources agree that of the two tissues, stromal hyperplasia predominates, but the exact ratio of the two is unclear. Anatomically the median and lateral lobes are usually enlarged, due to their highly glandular composition. The anterior lobe has little in the way of glandular tissue and is seldom enlarged.
Benign prostatic hyperplasia | Pathophysiology
The anterior pituitary is also known as the adenohypophysis, meaning "glandular undergrowth", from the Greek "adeno-" ("gland"), "hypo" ("under"), and "physis" ("growth").
Anterior pituitary | Etymology
The supraoccipital sits anterior to the paraoccipital. The size of the basioccipital is considered to be small. The majority of the occipital surface, posterior “horn”, and posterior lateral margins are made from the squamosal.
Burnetia | Description
Anterior () describes what is in front, and posterior () describes what is to the back of something. For example, in a dog the nose is anterior to the eyes and the tail is considered the most posterior part; in many fish the gill openings are posterior to the eyes but anterior to the tail. In projectional radiography terminology, an anteroposterior (AP) projection is taken with the X-ray generator anteriorly (such as in the front of a human), and the X-ray detector posteriorly. In contrast, a posteroanterior (PA) projection is taken with the X-ray generator posteriorly.
Anatomical terms of location | Anterior and posterior
In the occipital lobe, the lateral occipital sulcus, where present, divides the lateral, or middle occipital gyrus into a superior and an inferior part, which are then continuous in front with the parietal and temporal lobes. The anterior portion is often incomplete, but in some individuals it may encounter the superior temporal sulcus whilst the posterior portion originates from the middle of the curved lunate sulcus, or from a curved portion of the transverse occipital sulcus if absent.
Lateral occipital sulcus | Introduction
The posterior parietal cortex can be subdivided into the superior parietal lobule (Brodmann areas 5 + 7) and the inferior parietal lobule (39 + 40), separated by the intraparietal sulcus (IPS). The intraparietal sulcus and adjacent gyri are essential in guidance of limb and eye movement, and—based on cytoarchitectural and functional differences—is further divided into medial (MIP), lateral (LIP), ventral (VIP), and anterior (AIP) areas.
Parietal lobe | Structure
The head and segments of the antenna tend to be smaller in the holotype specimen while in the paratype they are slightly larger. The pubescence is short but scattered throughout the body, measuring . The colour of the specimens appears to be light-brown. The metapleural gland exhibits a notably wide and oval-shaped orifice, (openings into the body). The separation between the orifice and the posterior portion of the propodeum is twice the diameter than the orifice itself. The cuticle situated in the anterior portion (referring to what is in front) of the orifice is thinner in contrast to the cuticle surrounding the mesosoma, where it is notably transparent.
Sphecomyrma | "S. freyi"
This forms two chambers, one on either side of the visceral mass. The ingress chamber is anatomically anterior and the egress chamber is posterior. Within Ostreoidea, the degree of attachment of the left and right mantle lobes to the visceral mass varies between subgroups. The may be one (right) or two passages (left and right), or none, around the body between the adductor and hinge (termed either "supramyal" or "promial" passages).
Ostreoidea | Anatomy
The eyes protrude dorsally and laterally and a lack of hair was seen along the eyes. The postocular lobes were round in shape and not well defined. Adult males have short anal appendages that develop during the final instar phase of development.
Synthemiopsis | Description
(from Rushton, 1966, p.29) "In Pleuroctenium the anterior galabellar lobe is crescent-shaped and wrapped around the posterior glabellar lobe, the pygidial axis bears discrete spines, the borders and border-furrows are narrow, long spines are commonly developed and the surface is generally granulose".
Pleuroctenium | Diagnosis
Main article "Hypothalamic-pituitary-adrenal axis"
Anterior pituitary | Effects of the anterior pituitary
It is divided from rostral to caudal into two gyri: In macaque neuroanatomy, this region is often divided into caudal and rostral portions, cIPL and rIPL, respectively. The cIPL is further divided into areas Opt and PG whereas rIPL is divided into PFG and PF areas.
Inferior parietal lobule | Structure
Hormone secretion from the anterior pituitary gland is regulated by hormones secreted by the hypothalamus. Neuroendocrine cells in the hypothalamus project axons to the median eminence, at the base of the brain. At this site, these cells can release substances into small blood vessels that travel directly to the anterior pituitary gland (the hypothalamo-hypophyseal portal vessels). Aside from hypothalamic control of the anterior pituitary, other systems in the body have been shown to regulate the anterior pituitary’s function. GABA can either stimulate or inhibit the secretion of luteinizing hormone (LH) and growth hormone (GH) and can stimulate the secretion of thyroid-stimulating hormone (TSH).
Anterior pituitary | Role in the endocrine system
Ventral developmental patterning and the expression of transcription factors is influenced by the gradients of BMP2 and sonic hedgehog protein (SHH). These factors are essential for coordinating early patterns of cell proliferation. Six weeks into gestation, the corticotroph cells can be identified. By seven weeks of gestation, the anterior pituitary is capable of secreting ACTH. Within eight weeks of gestation, somatotroph cells begin to develop with cytoplasmic expression of human growth hormone. Once a fetus reaches 12 weeks of development, the thyrotrophs begin expression of Beta subunits for TSH, while gonadotrophs being to express beta-subunits for LH and FSH. Male fetuses predominately produced LH-expressing gonadotrophs, while female fetuses produce an equal expression of LH and FSH expressing gonadotrophs.
Development of the endocrine system | Pituitary gland
The pituitary gland is formed within the rostral neural plate. The Rathke’s pouch, a cavity of ectodermal cells of the oropharynx, forms between the fourth and fifth week of gestation and upon full development, it gives rise to the anterior pituitary gland. By seven weeks of gestation, the anterior pituitary vascular system begins to develop. During the first 12 weeks of gestation, the anterior pituitary undergoes cellular differentiation. At 20 weeks of gestation, the hypophyseal portal system has developed. The Rathke’s pouch grows towards the third ventricle and fuses with the diverticulum. This eliminates the lumen and the structure becomes Rathke’s cleft.
Development of the endocrine system | Pituitary gland
There is no membranous lobe that is turned backwards, but there is volsella with prominent lateral ridges.
Lasioglossum leucozonium | Males
The superior and middle frontal gyri are divided by the superior frontal sulcus. The middle and inferior frontal gyri are divided by the inferior frontal sulcus.
Frontal lobe | Structure
The staminodes occur posteriorly and have antherodes with four to six lobes. The stamens are anterior and are longer than the staminodes. The medial stamen differs in size and form from the lateral two, and when a central staminode is present it also differs from the other staminodes. The ovaries are bi- or trilocular and one to two ovules is present per locule.
Commelina | Description
In humans, the gene for the alpha subunit is located at cytogenetic location 6q14.3. It is expressed in two cell types, most notably the basophils of the anterior pituitary. The gene for the FSH beta subunit is located on chromosome 11p13, and is expressed in gonadotropes of the pituitary cells, controlled by GnRH, inhibited by inhibin, and enhanced by activin.
Follicle-stimulating hormone | Genes
There are many variants in the size and shape of the thyroid gland, and in the position of the embedded parathyroid glands. Sometimes there is a third lobe present called the "pyramidal lobe". When present, this lobe often stretches up the hyoid bone from the thyroid isthmus and may be one to several divided lobes. The presence of this lobe ranges in reported studies from 18.3% to 44.6%. It was shown to more often arise from the left side and occasionally separated. The pyramidal lobe is also known as Lalouette's pyramid. The pyramidal lobe is a remnant of the thyroglossal duct, which usually wastes away during the thyroid gland's descent.
Thyroid | Variation
The postsubiculum receives projections from the retrospleinal dysgranular cortex and the retrosplenial granular cortex A and B. The parasubiculum receives projections from the retrosplenial dysgranular cortex and retrosplenial granular cortex A. Caudal and lateral parts of the entorhinal cortex get projections from the retrosplenial dysgranular cortex, while the caudal medial entorhinal cortex receives projections from the retrosplenial granular cortex A. The retrosplenial dysgranular cortex sends projections to the perirhinal cortex. The retrospleinal granular cortex A sends projection to the rostral presubiculum.
Cingulate cortex | Outputs of the anterior cingulate gyrus
POMC, ACTH and β-lipotropin are secreted from corticotropes in the anterior lobe (or adenohypophysis) of the pituitary gland in response to the hormone corticotropin-releasing hormone (CRH) released by the hypothalamus. ACTH is synthesized from pre-pro-opiomelanocortin (pre-POMC). The removal of the signal peptide during translation produces the 241-amino acid polypeptide POMC, which undergoes a series of post-translational modifications such as phosphorylation and glycosylation before it is proteolytically cleaved by endopeptidases to yield various polypeptide fragments with varying physiological activity. These fragments include: In order to regulate the secretion of ACTH, many substances secreted within this axis exhibit slow/intermediate and fast feedback-loop activity.
Adrenocorticotropic hormone | Production and regulation
The anterior pituitary contains five types of endocrine cell, and they are defined by the hormones they secrete: somatotropes (GH); Lactotropes (PRL); gonadotropes (LH and FSH); corticotropes (ACTH) and thyrotropes (TSH). It also contains non-endocrine folliculostellate cells which are thought to stimulate and support the endocrine cell populations. Hormones secreted by the anterior pituitary are trophic hormones (Greek: trophe, “nourishment”). "Trophic hormones" directly affect growth either as hyperplasia or hypertrophy on the tissue it is stimulating. "Tropic hormones" are named for their ability to act directly on target tissues or other endocrine glands to release hormones, causing numerous cascading physiological responses.
Anterior pituitary | Function
Gonadotropin-releasing hormone (GnRH) is secreted from the hypothalamus by GnRH-expressing neurons. The anterior portion of the pituitary gland produces luteinizing hormone (LH) and follicle-stimulating hormone (FSH), and the gonads produce estrogen and testosterone.
Hypothalamic–pituitary–gonadal axis | Introduction
The dorsal subiculum sends projections to retrosplenial granular cortex B, while ventral subiculum sends projections to retrosplenial granular cortex A. Entorhinal cortex – caudal parts – sends projections to the retrosplenial dysgranular cortex.
Cingulate cortex | Inputs of the anterior cingulate gyrus
Four of the six anterior pituitary hormones are tropic hormones that regulate the function of other endocrine organs. Most anterior pituitary hormones exhibit a diurnal rhythm of release, which is subject to modification by stimuli influencing the hypothalamus.
Endocrine gland | Introduction
The inferior parietal lobule is further subdivided into the supramarginal gyrus, the temporoparietal junction, and the angular gyrus. The inferior parietal lobule corresponds to Brodmann areas 39 and 40.
Posterior parietal cortex | Anatomy
The cause of hyperpituitarism in most cases is due to pituitary adenomas. They usually come from the anterior lobe, are functional and secrete the hormone, GH and prolactin.
Hyperpituitarism | Cause
The anterior/posterior patterning of the embryo occurs sometime before or during gastrulation. The first cells to involute have anterior inducing activity while the last cells have posterior inducing activity. The anterior inducing ability comes from the Xwnt-8 antagonizing signals Cereberus, Dickkopf and Frzb discussed above. Anterior head development also requires the function of IGFs (insulin-like growth factors) expressed in the dorsal midline and the anterior neural tube. It is believed that IGFs function by activating a signal transduction cascade that interferes and inhibits both Wnt signaling and BMP signaling. In the posterior, two candidates for posteriorizing signals include eFGF, a fibroblast growth factor homologue, and retinoic acid.
Regional differentiation | Anterior/posterior axis
This variant has not been identified, but it has been suggested to coincide with a 22 kDa glycosylated variant of 23 kDa identified in the pituitary gland. Furthermore, these variants circulate partially bound to a protein (growth hormone-binding protein, GHBP), which is the truncated part of the growth hormone receptor, and an acid-labile subunit (ALS).
Growth hormone | Structure
Almost identical to Archaeagnostus, but the frontal lobe of the central raised area of the cephalon (or glabella) is effaced, while the back of glabella is inflated.
Eoagnostus | Description
The "torpedo" receptor is found in all follicle cells; however, the "gurken" signal is only found on the anterior dorsal side of the oocyte. The follicle cells change shape and synthetic properties to distinguish the dorsal side from the ventral side. These dorsal follicle cells are unable to produce the pipe protein required for step two. The second step is a signal from the ventral follicle cells back to the oocyte. This signal acts after the egg has left the follicle cells so this signal is stored in the perivitelline space. The follicle cells secrete "windbeutel," "nudel," and "pipe," which create a protease-activating complex.
Regional differentiation | Dorsal/ventral axis
The proximal straight section is divided into three longitudinal lobes: a smooth lobe on either side and a transversely ridged lobe running between them. The middle ridged lobe is made up of raised "rugae" and deep "interstices", which Sharov compared to rosary beads. The distal section is thought to be an extension of the middle and anterior lobes of the proximal section. While the anterior lobe widens in the distal section, the posterior lobe of the proximal section narrows until it ends at the base of the distal section. In addition, an "anterior flange" appears about two-thirds the way up the proximal section and continues to the tip of the distal section.
Longisquama | Integumentary structures
-- Method for Heating the Preoptic Anterior Hypothalamus
Preoptic anterior hypothalamus | References
The FPN is primarily composed of the rostral lateral and dorsolateral prefrontal cortex (especially the middle frontal gyrus) and the anterior inferior parietal lobule. Additional regions include the middle cingulate gyrus and potentially the dorsal precuneus, posterior inferior temporal lobe, dorsomedial thalamus and the head of the caudate nucleus.
Frontoparietal network | Anatomy
Whichever cell aligns anteriorly will become the otolith, while the posterior cell will form the ocellus. In the absence of cell-cell interactions both cells develop into ocelli, which is the default fate.
Equivalence group | Introduction
Deficiency of all anterior pituitary hormones is more common than individual hormone deficiency. Deficiency of luteinizing hormone (LH) and follicle-stimulating hormone (FSH), together referred to as the gonadotropins, leads to different symptoms in men and women. Women experience oligo- or amenorrhea (infrequent/light or absent menstrual periods respectively) and infertility. Men lose facial, scrotal and trunk hair, as well as suffering decreased muscle mass and anemia. Both sexes may experience a decrease in libido and loss of sexual function, and have an increased risk of osteoporosis (bone fragility). Lack of LH/FSH in children is associated with delayed puberty. Growth hormone (GH) deficiency leads to a decrease in muscle mass, central obesity (increase in body fat around the waist) and impaired attention and memory.
Hypopituitarism | Anterior pituitary
The posterior cingulate cortex (Brodmann's area 23) sends projections to dorsolateral prefrontal cortex (Brodmann's area 9), anterior prefrontal cortex (Brodmann's area 10), orbitofrontal cortex (Brodmanns’ area 11), the parahippocampal gyrus, posterior part of the inferior parietal lobule, the presubiculum, the superior temporal sulcus and the retrosplenial region. The retrosplenial cortex and caudal part of the cingulate cortex are connected with rostral prefrontal cortex via cingulate fascicule in macaque monkeys Ventral posterior cingulate cortex was found to be reciprocally connected with the caudal part of the posterior parietal lobe in rhesus monkeys. Also the medial posterior parietal cortex is connected with posterior ventral bank of the cingulate sulcus.
Cingulate cortex | Outputs of the posterior cingulate gyrus
Posterior cortex usually means the posterior (back) part of the complete cerebral cortex and includes the occipital, parietal, and temporal cortices. In other words, the posterior cortex includes all the cerebral cortex without the frontal cortex. In combination with specific cortical areas, 'posterior cortex' usually refers to the posterior (back) part of that cortical area. For example: the posterior parietal cortex is the posterior part of the parietal cortex and the posterior cingulate cortex is the posterior part of the cingulate cortex.
Posterior cortex | Introduction
The base of the genal spine is equally far from the midline as the base of the intergenal angle. The most backwards spines (or intergenal spines) are prominent too, pointing backwards and outwards at about 45° compared to the midline. The intergenal angle is opposite the middle of the occipital ring (L0). The rounded ridge that borders the cephalon (or cephalic border) and the frontal lobe (L4) of the raised central part of the cephalon (or glabella) touch. L4 bulges out the plain where cephalon rests. L4 is wider than the rearmost ring of the glabella (L0); L4 has the same length of L0 and L1 together.
Lochmanolenellus | Description
Pulvinar means pillow in Latin. It constitutes the posterior pole of the thalamus and its posterior border is indeed smooth. Anteriorly there is only an incomplete boundary with the medial nucleus. The two have in fact common connections both thalamocortical and corticothalamic. This is the case for instance for the frontal cortex. The usual subdivisions do not fit with the distribution of cortical afferent. It is common to find the description of a "nucleus lateralis posterior ( LP). This is simply a part of the pulvinar passing over the lateral region and giving in transverse sections the image of a ventral and a dorsal (or lateral) subdivision.
Isothalamus | Posterior region. Pulvinar. Pu (with "LP" as a part)
Head shape is circular with posterior margin flat to feebly concave medially in full-face view. Antenna is 11-segmented with apical three segments forming a distinct club. Antennal insertion is surrounded by a raised and unbroken lamella. Frontal carina is distinct and extends just past the level of the posterior eye margin. Weak median carina, approximately same length as terminal antennal segment, extending posteriorly from between antennal insertions and transitioning into a weak median groove that terminates near eye level. Frontal lobe is weakly expanded as a thin lamella. Eye moderate-sized, approximately same size as antennal socket, 3–4 facets along longest diameter.
Pristomyrmex tsujii | Workers
The headshield (or cephalon) is not semi-circular but near pentangular, about 1¼ times wider than long. The front has a blunt angle at midline. The most frontal spines (or genal spines) are prominent, pointing backwards and outwards at about 65° compared to the midline. The genal angle (between the back of the spine and the cephalic border to the rear of the spine) is opposite the furrow between L2 and L3 – the scientific convention is to count glabellar lobes back to front, giving them the following names: occipital ring or lobe (OR, OL or L0), 1st lobe (L1), 2nd lobe (L2), 3rd lobe (L3), and anterior lobe (AL or L4).
Lochmanolenellus | Description
Rathke's pouch, and therefore the anterior pituitary, is derived from ectoderm. The pouch eventually loses its connection with the pharynx giving rise to the anterior pituitary. The anterior wall of Rathke's pouch proliferates, filling most of the pouch to form "pars distalis" and "pars tuberalis". The posterior wall forms "pars intermedia". In some organisms, the proliferating anterior wall does not fully occupy Rathke's pouch, leaving a remnant (Rathke's cleft) between the "pars distalis" and "pars intermedia".
Rathke's pouch | Development
The excretory pore is posterior to median bulb. The esophageal gland is lobe-like and extends anteriorly over the intestine. The tail is 115-189 micrometers long with a rounded terminus. Males: Outline of lip region is more flattened at the sides than in females but arrangement of lobes is similar. The testis is outstretched. Spicules are arcuate with ventral flanges and the distal ends pointed with small apical notches. The gubernaculum is well developed and there is a bursa enveloping the tail. Female: The vulva is a transverse slit and the vulval lips do not protrude into the vagina which generally has an opposing pair of sclerotized pieces in the lateral view.
Belonolaimus longicaudatus | Description
It is a triangular mass with one vertex at the buccinators, one at the levator labii superioris alaeque nasi, and one at the orbicularis oris. The intermediate lobe lies between the anterior and posterior lobes over the maxilla. The intermediate lobe seems to lose a significant amount of volume between childhood and adulthood. The posterior lobe of the buccal fat pad runs from the infraorbital fissure and temporal muscle to the upper rim of the mandible and back to the mandibular ramus.
Buccal fat pad | Nomenclature and structure
"Condylopyge" is isopygous with cephalon and pygidium of approximately equal size. The characteristic lateral expansion of the frontal glabellar lobe, occipital structures, and pygidial axis with three pairs of lateral lobes and a terminal piece differentiate Condylopygidae from all other agnostids. "Condylopyge" is easily distinguished from its sister taxon, "Pleuroctenium", because the frontal glabellar lobe does not extend partially around the posterior glabellar lobe. Furthermore the frontal glabellar lobe is never bisected medially as in "Pleuroctenium". The pygidium may carry a pair of backwardly directed spines, but this also occurs regularly in "Pleuroctenium".
Condylopyge | Description
Hypothalamic–pituitary hormones are hormones that are produced by the hypothalamus and pituitary gland. Although the organs in which they are produced are relatively small, the effects of these hormones cascade throughout the body. They can be classified as a hypothalamic–pituitary axis (HP axis) of which the adrenal (), gonadal (), thyroid (), somatotropic (), and prolactin () axes are branches. It is possible for the function of these hormones to be altered by physical activity.. In posterior pituitary we have hormones that control absorption of water and oxytocin.
Hypothalamic–pituitary hormone | Introduction
Somatotropic cells constitute 20% of anterior pituitary cells. They release growth hormone (GH) in response to Growth hormone releasing hormone (GHRH, or somatocrinin) or are inhibited by GHIH (somatostatin), both received from the hypothalamus via the hypophyseal portal system vein and the secondary plexus.
Somatotropic cell | Structure
It has three distinct pairs of lobes, and is defined by shallow furrows. The forward lobe of the rhachis (M1) is a bit shorter and wider than the middle lobe (M2) and separated from it by a furrow (F1) which is directed outward and slightly backward from the dorsal furrow, and then curved strongly forward adaxially. The rear lobe (M3) is – longer than both others together, and the furrow is directed outward and slightly forward from the dorsal furrow. The middle lobe has a prominent tubercle, which extends backwards above the anterior portion of rear lobe. It is the highest point of the pygidium.
Geragnostus | Description
Development appears critically sensitive to gene dosage, and variation in the normal level of transcription factor activity causes a range of anterior segment anomalies. Interplay between "PITX2" and "FOXC1" in the development of different anterior segment tissues may partly explain the phenotypic variability and the genetic heterogeneity characteristic of ASD. In the most recent research, the "PAX6" gene has been implicated in Peters' Anomaly
Anterior segment mesenchymal dysgenesis | Pathophysiology
The eye-lobe (or ocular lobe) is stocky, reaching no further back than the furrow between L2 and L3. The medial part of posterior border flexing gently backwards.
Lochmanolenellus | Description
(The two nuclei are related in space, but not in function.) It is uncertain whether fibers are continued directly from the gracile and cuneate fasciculi into the inferior peduncle.
Spinocerebellar tract | Posterior external arcuate fibers
The posterior lobe of cerebellum or neocerebellum, is the portion of the cerebellum below the primary fissure. It is sometimes called the neocerebellum since phylogenetically it is the newest part of the cerebellum. It plays an important role in fine motor coordination, specifically in the inhibition of involuntary movement via inhibitory neurotransmitters, especially GABA. The posterior lobe receives input mainly from the brainstem (i.e., reticular formation and inferior olivary nucleus) and cerebral cortex.
Posterior lobe of cerebellum | Introduction
Thyrotropes (also called thyrotrophs) are endocrine cells in the anterior pituitary which produce thyroid stimulating hormone (TSH) in response to thyrotropin releasing hormone (TRH). Thyrotropes consist around 5% of the anterior pituitary lobe cells. Thyrotropes appear basophilic in histological preparations.
Thyrotropic cell | Introduction
The pars tuberalis is part of the anterior lobe of the pituitary gland, and wraps the pituitary stalk in a highly vascularized sheath.
Pars tuberalis | Introduction
The aciniform glands are connected to the median (18–24 in females and 14–20 in males) and posterior spinnerets (60 in either sex).
Oxytate | Anatomy
Brain areas in the parietal lobes play an integral role in processing and interpreting somatic sensations from the body or environment. The right parietal lobe is associated with sensory integration and perception whereas the left parietal lobe is believed to function at a more conceptual level involving speech, reading and writing. The central sulcus divides the frontal lobe from the parietal lobe which is located superior to the occipital lobe and posterior to the frontal lobe. The primary somatosensory cortex- the main processing center for tactile sensations- is positioned posterior to the central sulcus, on the post-central gyrus. The somatosensory system is also associated with the perception of temperature, taste, vision, proprioception and kinesthesia.
Amorphosynthesis | Anatomy
The two lobes differ slightly in size, with the left lobe usually higher than the right. Thymic tissue may be found scattered on or around the gland, and occasionally within the thyroid. The thymus in children stretches variably upwards, at times to as high as the thyroid gland.
Thymus | Variation
A third type of pituitary adenoma secretes excess ACTH, which in turn, causes an excess of cortisol to be secreted and is the cause of Cushing's disease.
Anterior pituitary | Increased activity
Sagittal sections show that the pulvinar(LP) ensemble is a single curved entity. The whole receives in the same almost identical afferences. A main medial part receives flat islands of axonal terminations from the frontal, parietal, temporal and preoccipital cortex. Only one part of the pulvinar is particular, the intergeniculate or inferior pulvinar, which receives tectal afferents and which has a visuotopic map.
Isothalamus | Posterior region. Pulvinar. Pu (with "LP" as a part)
The posterior parietal cortex (PPC) receives somatosensory and visual input, which then, through motor signals, controls movement of the arm, hand, and eyes. Various studies in the 1990s found that different regions of the posterior parietal cortex in macaques represent different parts of space.
Parietal lobe | Function
The lateral region and the geniculate bodies indeed receive strong lower "specific" afferences and can be seen as the "sensorimotor" part of the thalamus. The medioposterior ensemble, in most of its volume does not receive subcortical afferents and abundant afferences from the "associative" cortex but in some, essentially ventral parts, in fact receives subcortical afferences, such as tectal, spinothalamic or amygdalar. The anterior region receives a particular afference that is not entirely subcortical (directly or indirectly from the subiculum).
Isothalamus | Isothalamic parts or regions
In "Pentagenia", this frontal process comes to a point.
Hexagenia | General information
Each type of cell behaves differently in response to FSH. Theca interna cells express receptors for luteinizing hormone (LH). LH induces the production of androgens by the theca cells, most notably androstendione, which are aromatized by granulosa cells to produce estrogens, primarily estradiol. Consequently, estrogen levels begin to rise.
Folliculogenesis | Early tertiary
Narrow eye ridges emerge from the back of the frontal lobe outward and slightly backward (± 20°). Thorax of 5 or 6 segments. Pygidium approximately the same size (isopygous) or larger (macropygous) than the cephalon, with an axis of 6 to 12 rings, and clear pleural furrows. The border is lacking or hair thin. The surface may be smooth or has granules.
Ovatoryctocara | Description
The term posterior horn (also dorsal horn, posterior cornu, dorsal cornu) may refer to:
Posterior horn | Introduction
This individual's existence would not change the fact that the groups on average were quite different from one another, and that these differences were statistically significant. A later report by Byne et al. (2001) noted that We also measured the anterior commissure in the same blocks of tissue used for the present hypothalamic study (data not shown) and were unable to replicate a report [by Allen and Gorski] that its cross-sectional area is larger in women than in men. Also, a study by Lasco et al. (2002) said:We examined the cross-sectional area of the AC in postmortem material from 120 individuals, and found no variation in the size of the AC with age, HIV status, sex, or sexual orientation.
Anterior commissure | Sexuality