Effects of preoptic injections of gastrin, cholecystokinin, secretin, vasoactive intestinal peptide and PHI on the secretion of luteinizing hormone and prolactin in ovariectomized estrogen-primed rats.
The effects of intracerebral injections of brain-gut peptides in the preoptic region on the secretion of luteinizing hormone (LH) and prolactin (PRL) were examined in ovariectomized, estrogen-primed rats. Gastrin or cholecystokinin-octapeptide injection in the preoptic region induced a moderate increase of circadian rise of LH secretion in some animals but no appreciable change in PRL secretion. Secretin injection was strikingly effective in increasing circadian rise of LH and PRL secretion. Vasoactive intestinal peptide injection completely abolished the occurrence of circadian rise of LH secretion whereas PHI injection facilitated LH secretion undergoing the circadian rhythm. The results suggest that those peptides act as neurotransmitters or neuromodulators in the preoptic region and are implicated in the regulation of LH and PRL secretion.
D000818:Animals; D002766:Cholecystokinin / Q000494:pharmacology; D002940:Circadian Rhythm / Q000187:drug effects; D004967:Estrogens / Q000494:pharmacology; D005260:Female; D005755:Gastrins / Q000494:pharmacology; D007986:Luteinizing Hormone / Q000097:blood / Q000378:metabolism*; D009479:Neuropeptides / Q000494:pharmacology*; D010052:Ovariectomy; D011301:Preoptic Area / Q000187:drug effects*; D011388:Prolactin / Q000097:blood / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012633:Secretin / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D004967:Estrogens; D005755:Gastrins; D009479:Neuropeptides; D012633:Secretin; D014660:Vasoactive Intestinal Peptide; D011388:Prolactin; D007986:Luteinizing Hormone; D002766:Cholecystokinin