title: Opioid modulation of vasopressin secretion in conscious rats.
abstract: To clarify the role of endogenous opioid peptides in the control of vasopressin (AVP) secretion, the effects of an endogenous kappa-agonist, leumorphin, derived from proenkephalin B and an opioid antagonist, naloxone, on AVP secretion were examined in conscious and freely moving rats. Intraperitoneal injection of nicotine markedly increased AVP secretion in rats. The nicotine-induced AVP secretion was significantly suppressed by intracerebroventricular (i.c.v.) pretreatment with leumorphin. Intravenous injection of naloxone significantly increased the basal AVP level and carbachol-induced AVP secretion. These results indicate that endogenous opioid peptides have an inhibitory effect on AVP secretion in rats.
authors.affiliation: Second Division, Department of Medicine, Kyoto University School of Medicine, Japan.
authors.forename: T
authors.initials: T
authors.lastname: Yamada
authors.forename: K
authors.initials: K
authors.lastname: Nakao
authors.forename: H
authors.initials: H
authors.lastname: Itoh
authors.forename: G
authors.initials: G
authors.lastname: Shirakami
authors.forename: A
authors.initials: A
authors.lastname: Sugawara
authors.forename: Y
authors.initials: Y
authors.lastname: Saito
authors.forename: M
authors.initials: M
authors.lastname: Mukoyama
authors.forename: H
authors.initials: H
authors.lastname: Arai
authors.forename: K
authors.initials: K
authors.lastname: Hosoda
authors.forename: N
authors.initials: N
authors.lastname: Morii
mesh_terms: D000818:Animals; D001794:Blood Pressure / Q000187:drug effects; D002217:Carbachol / Q000494:pharmacology; D004723:Endorphins / Q000502:physiology*; D004745:Enkephalins / Q000494:pharmacology; D006339:Heart Rate / Q000187:drug effects; D008297:Male; D009270:Naloxone / Q000494:pharmacology; D009538:Nicotine / Q000494:pharmacology; D011498:Protein Precursors / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D014667:Vasopressins / Q000378:metabolism*
chemical_list: D004723:Endorphins; D004745:Enkephalins; D011498:Protein Precursors; D014667:Vasopressins; D009270:Naloxone; D009538:Nicotine; D002217:Carbachol; C033660:preproenkephalin