  By using bidimensional spectral data obtained at the 6m telescope for the
Virgo spirals NGC 4216 and NGC 4501, we have found chemically distinct
metal-rich nuclei in these galaxies. Under the assumption of equal ages for the
nuclear and bulge stellar populations, the metallicity difference between the
nuclei and their environments in the galaxies is estimated as a factor of 2.
But we have also found an age difference between the nucleus and the bulge in
NGC 4216: age-metallicity disentangling on the diagrams (H-beta, Mgb), (H-beta,
[MgFe]), and (H-beta, $<Fe>$) results in an age estimate for the nucleus of 8 -
12 billion years, the bulge being older by a factor of 1.5 - 2; and the
self-consistent metallicity difference estimate is then a factor of 3. The
solar magnesium-to-iron ratios in the galactic nuclei show evidence for a long
duration of the secondary nuclear star formation bursts which produced the
chemically distinct stellar subsystems. Detailed morphological and kinematical
analyses made for the stellar and gaseous structures in the centers of NGC 4216
and 4501 have revealed the presence of circumnuclear stellar-gaseous disks with
radius of some hundreds parsecs which demonstrate fast axisymmetric rotation
and lie exactly in the planes of the main galactic disks.
