Dopamine inhibits in vitro release of VIP and proliferation of VIP-immunoreactive pituitary cells.
A double immunohistochemical study for VIP and proliferating cell nuclear antigen (PCNA) was carried out on monolayer cultures from adult male rats pituitary glands treated with dopamine (ranging from 10(-9) to 10(-5) M), in order to establish whether or not dopamine is involved in the regulation of the proliferation rate of pituitary VIP-immunoreactive cells. For all doses of dopamine assayed, the release of VIP to the culture medium, the numerical density of VIP-immunoreactive cells and the percentages of VIP- and PCNA-immunoreactive cells decreased significantly after dopamine treatment. These results suggest that dopamine could be a physiological inhibitor involved in the modulation of pituitary VIP proliferation rate.
Carretero
J
J
Department of Human Anatomy and Histology, Universidad de Salamanca, Spain.
Vazquez
R J
RJ
Santos
M
M
Cacicedo
L
L
Rubio
M
M
Sanchez-Franco
F
F
Vazquez
R
R
D000818:Animals; D002455:Cell Division / Q000187:drug effects; D002478:Cells, Cultured; D004298:Dopamine / Q000494:pharmacology*; D007150:Immunohistochemistry; D008297:Male; D010902:Pituitary Gland / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D011863:Radioimmunoassay; D051381:Rats; D017208:Rats, Wistar; D014660:Vasoactive Intestinal Peptide / Q000378:metabolism*
D018809:Proliferating Cell Nuclear Antigen; D014660:Vasoactive Intestinal Peptide; D004298:Dopamine