Immunocytochemical localization of vasoactive intestinal peptide and neuropeptide Y in the bovine ovary.
The distribution of the neuropeptides vasoactive intestinal peptide (VIP) and neuropeptide Y (NPY) was studied immunocytochemically in bovine ovaries from 3 mo of gestation up to and including puberty, and from adult cows at three stages of the estrous cycle. The appearance of VIP and NPY immunoreactivity of 4.5-6 mo of gestation coincided with the onset of follicular development. In contrast to NPY, VIP was first found in the cortex. Both VIP and NPY immunoreactivity increased with age. From 9 mo of gestation onwards, VIP and NPY were found around blood vessels and non-vascular smooth muscle cells, in the stroma near preantral follicles, and in the theca externa of antral follicles. In addition, VIP-positive cells were observed exclusively in the granulosa layer of the preovulatory follicle at the time of the LH surge. The distribution of VIP- and NPY-immunoreactive fibers in the ovary may point to an effect of these neuropeptides on various physiological processes, including follicle development and ovarian blood flow. In addition, the presence of VIP-positive cells in the granulosa layer of the preovulatory follicle is indicative of a role for VIP in ovulation.
Hulshof
S C
SC
Department of Functional Morphology, Faculty of Veterinary Medicine, Utrecht University, The Netherlands.
Dijkstra
G
G
Van der Beek
E M
EM
Bevers
M M
MM
Figueiredo
J R
JR
Beckers
J F
JF
Van den Hurk
R
R
D000375:Aging; D000818:Animals; D002417:Cattle / Q000378:metabolism*; D004971:Estrus; D005260:Female; D005865:Gestational Age; D007150:Immunohistochemistry; D009478:Neuropeptide Y / Q000032:analysis*; D009866:Oogenesis; D006080:Ovarian Follicle / Q000196:embryology / Q000502:physiology; D010053:Ovary / Q000737:chemistry* / Q000196:embryology / Q000254:growth & development; D012741:Sexual Maturation; D014018:Tissue Distribution; D014660:Vasoactive Intestinal Peptide / Q000032:analysis* / Q000502:physiology
D009478:Neuropeptide Y; D014660:Vasoactive Intestinal Peptide