Effect of acetylcholine and 5-hydroxytryptamine on the secretion of corticotrophin-releasing factor-41 and arginine vasopressin from the rat hypothalamus in vitro.
Previous studies using the isolated rat hypothalamus in vitro have shown that both acetylcholine and 5-hydroxytryptamine (5-HT) stimulate the secretion of bioactive corticotrophin-releasing factor (CRF). However, the CRF complex consists of a number of bioactive substances, and in this study we examined the effect of acetylcholine and 5-HT on the release of immunoreactive (ir)-CRF-41 and ir-arginine vasopressin (AVP) in vitro. Acetylcholine caused a dose-dependent (10 pmol-10 nmol/l) release of both neuropeptides, and the effect was partially antagonized by both atropine and hexamethonium. Nicotine (0.1-10 mumol/l) also stimulated the release of both peptides, whereas bethanacol had no effect on AVP release, but had a variable action on CRF-41 release. 5-HT caused a dose-dependent (10 pmol-1 nmol/l) stimulation of CRF-41 release without any effect on AVP release, and this effect was antagonized by cyproheptadine, suggesting the participation of specific 5-HT receptors.
Hillhouse
E W
EW
Department of Medicine, King's College School of Medicine and Dentistry, Denmark Hill, London.
Milton
N G
NG
D000109:Acetylcholine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D000818:Animals; D001127:Arginine Vasopressin / Q000378:metabolism*; D001285:Atropine / Q000494:pharmacology; D003346:Corticotropin-Releasing Hormone / Q000037:antagonists & inhibitors / Q000378:metabolism*; D003533:Cyproheptadine / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D018738:Hexamethonium; D006584:Hexamethonium Compounds / Q000494:pharmacology; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D066298:In Vitro Techniques; D008297:Male; D009538:Nicotine / Q000494:pharmacology; D010446:Peptide Fragments / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains; D012701:Serotonin / Q000494:pharmacology*
D006584:Hexamethonium Compounds; D010446:Peptide Fragments; D001127:Arginine Vasopressin; D003533:Cyproheptadine; D012701:Serotonin; D018738:Hexamethonium; D009538:Nicotine; D001285:Atropine; D003346:Corticotropin-Releasing Hormone; C045089:corticotropin releasing hormone (9-41); D000109:Acetylcholine