Centrally injected CDP-choline increases plasma vasopressin levels by central cholinergic activation


Cavun S., Savci V., Ulus I.

FUNDAMENTAL & CLINICAL PHARMACOLOGY, vol.18, no.1, pp.71-77, 2004 (Peer-Reviewed Journal) identifier identifier identifier

  • Publication Type: Article / Article
  • Volume: 18 Issue: 1
  • Publication Date: 2004
  • Doi Number: 10.1046/j.0767-3981.2003.00213.x
  • Journal Name: FUNDAMENTAL & CLINICAL PHARMACOLOGY
  • Journal Indexes: Science Citation Index Expanded, Scopus
  • Page Numbers: pp.71-77

Abstract

In the present study, both the effects of intracerebroventricular (i.c.v.) injection of cytidine-5'-diphosphate choline (CDP-choline) on plasma vasopressin levels and the choline involvement of these effects were investigated. I.c.v. administration of CDP-choline (0.5, 1.0 and 2.0 mumol) increased plasma vasopressin levels dose- and time-dependently. I.c.v. injection of equimolar dose of choline (1 mumol) produced similar vasopressin response. However equimolar dose of cytidine (1 mumol; i.c.v.), the other hydrolysis product of CDP-choline, did not affect plasma vasopressin levels. Pretreatment of rats with hemicholinium-3, neuronal high affinity choline uptake inhibitor (20 mug; i.c.v.) blocked the vasopressin response to i.c.v. CDP-choline (1 mumol). Pretreatment of rats with mecamylamine (50 mug; i.c.v.), a nonselective nicotinic receptor antagonist, abolished the increase in plasma vasopressin induced by CDP-choline while atropine (10 mug; i.c.v.), nonselective muscarinic receptor antagonist, failed to change the response. In conclusion, intracerebroventricularly injected CDP-choline can increase plasma vasopressin levels by activating central nicotinic cholinergic receptors through the activation of presynaptic cholinergic mechanisms.