Growth hormone (GH) is a peptide hormone that stimulates growth, cell reproduction and regeneration in humans and other animals. Growth hormone is a 191-amino acid, single-chain polypeptide that is synthesized, stored, and Secreted by the somatotroph cells within the lateral wings of the anterior pituitary gland. Somatotropin (STH) refers to the growth hormone produced naturally in an animals, Whereas the term somatropin refers to growth hormone produced by recombinant DNA technology, and is abbreviated "HGH" in humans.