Multiple effects of neuropeptide Y, substance P and vasoactive intestinal polypeptide on progesterone and oxytocin release from bovine corpus luteum in vitro.
Recent observations indicate that the rat ovary receives not only adrenergic but also peptidergic innervation. In ruminants, there are few data available on the extent of a possible direct regulation of the peptidergic innervation of the ovary including the corpus luteum (CL). The direct effects of neuropeptide Y (NPY), substance P (SP) and vasoactive intestinal polypeptide (VIP) on the release of progesterone and oxytocin from midluteal phase CL (days 8-12) were examined in vitro. A possible direct neural influence might provide a sensitive short-term control. Long-term as well as short-term effects were assessed using both a serum-reduced luteal cell culture and a microdialysis system (MDS) of luteal tissue. In the long-term experiments, luteal cells were preincubated from the start of the culture for 48 h with NPY, SP and VIP (10 pmol/1-100 nmol/l). During the following 4 h the neuropeptides showed a dose-dependent stimulation of progesterone release, but there was no effect on oxytocin release. LH showed a synergistic effect with NPY, SP and VIP on progesterone release. In the short-term experiments, the neuropeptides were added 48 h after the start of the culture. All three peptides were most stimulatory to LH-supported progesterone release 30 min after addition, and the effect decreased greatly thereafter to the control level from 60 to 120 min. In contrast, LH alone induced the maximal progesterone stimulation at 120 min. In the MDS, a 30-min perfusion with NPY, SP or VIP (10 nmol/l, 100 nmol/l and 1 mumol/l) induced significant acute effects on progesterone and oxytocin release.(ABSTRACT TRUNCATED AT 250 WORDS)
Miyamoto
A
A
Institute of Physiology, Technical University of Munich, Freising-Weihenstephan, Germany.
Brückmann
A
A
von Lützow
H
H
Schams
D
D
D000818:Animals; D002417:Cattle / Q000378:metabolism*; D002478:Cells, Cultured; D003338:Corpus Luteum / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D005260:Female; D009478:Neuropeptide Y / Q000494:pharmacology; D009479:Neuropeptides / Q000494:pharmacology*; D010121:Oxytocin / Q000378:metabolism*; D011374:Progesterone / Q000378:metabolism*; D013373:Substance P / Q000494:pharmacology; D013997:Time Factors; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D009478:Neuropeptide Y; D009479:Neuropeptides; D013373:Substance P; D014660:Vasoactive Intestinal Peptide; D011374:Progesterone; D010121:Oxytocin