Neural mechanism of the antisecretory effect of peptide YY in the rat colon in vivo.
The purpose of this work was to determine the mechanism of the antisecretory effect of peptide YY in the rat colon and whether this effect is physiological. In this prospect, doses of exogenous peptide YY producing physiological and supraphysiological plasma levels were intravenously infused in rats provided with colonic and jejunal ligated loops in vivo, under secretory stimulation by vasoactive intestinal peptide. Peptide YY decreased the secretory effect of VIP in a dose-related fashion. The effect of peptide YY was blocked or strongly decreased by tetrodotoxin, hexamethonium, idazoxan, haloperidol, and the sigma antagonist BMY 14, 802 in both the colon and jejunum. We conclude that peptide YY decreases water and electrolyte secretion in the colonic mucosa by a complex neural mechanism involving at least two neurons connected through a nicotinic synapse, alpha-2 adrenoceptors and sigma receptors, and that this effect can occur with physiological doses of peptide YY.
Chariot
J
J
Institut National de la Santé et de la Recherche Médicale U410, Faculté de Médecine X. Bichat, BP 416, 75870, Paris, France.
Tsocas
A
A
Souli
A
A
Presset
O
O
Rozé
C
C
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D001834:Body Water / Q000187:drug effects / Q000378:metabolism; D003106:Colon / Q000187:drug effects* / Q000378:metabolism*; D018492:Dopamine Antagonists / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006220:Haloperidol / Q000494:pharmacology; D018738:Hexamethonium / Q000494:pharmacology; D019329:Idazoxan / Q000494:pharmacology; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism; D007583:Jejunum / Q000187:drug effects / Q000378:metabolism; D008297:Male; D018733:Nicotinic Antagonists / Q000494:pharmacology; D019894:Peptide YY / Q000008:administration & dosage / Q000494:pharmacology* / Q000502:physiology; D051381:Rats; D017208:Rats, Wistar; D026941:Sodium Channel Blockers; D013779:Tetrodotoxin / Q000494:pharmacology; D014660:Vasoactive Intestinal Peptide / Q000494:pharmacology
D000317:Adrenergic alpha-Antagonists; D018492:Dopamine Antagonists; D018733:Nicotinic Antagonists; D026941:Sodium Channel Blockers; D019894:Peptide YY; D014660:Vasoactive Intestinal Peptide; D018738:Hexamethonium; D013779:Tetrodotoxin; D006220:Haloperidol; D019329:Idazoxan