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NASA NTRS · 20040142188

Non-NMDA receptor antagonist-induced drinking in rat

Xu, Z.·Johnson, A. K.
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Abstract

Glutamate has been implicated in the central control of mechanisms that maintain body fluid homeostasis. The present studies demonstrate that intracerebroventricular (i.c.v.) injections of the non-N-methyl-d-aspartate (NMDA) receptor antagonists 6, 7-dinitroquinoxaline-2,3-dione (DNQX) and 6-cyano-7-nitroquinoxaline-2,3 dione (CNQX) induce drinking in rats. The dipsogenic effect of i.c.v. DNQX was antagonized by the non-NMDA receptor agonist alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA). The water intake induced by DNQX was also blocked by pretreatment with a NMDA receptor antagonist, MK-801, but not by angiotensin type 1 (AT1) or acetylcholine muscarinic receptor antagonists (losartan and atropine). The results indicate that non-NMDA receptors may exert a tonic inhibitory effect within brain circuits that control dipsogenic activity and that functional integrity of NMDA receptors may be required for the non-NMDA receptor antagonists to induce water intake. Copyright 1998 Published by Elsevier Science B.V.

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Non-NASA CenterNASA Discipline Regulatory PhysiologyCerebral Ventricles/drug effects/physiologyDrinking Behavior/drug effects/physiology6-Cyano-7-nitroquinoxaline-2,3-dione/administration & dosage/pharmacologyQuinoxalines/administration & dosage/pharmacologyExcitatory Amino Acid Antagonists/administration & dosage/pharmacologyAnimalsalpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid/pharmacologyDizocilpine Maleate/pharmacologyInjections, IntraventricularExcitatory Amino Acid Agonists/pharmacologyRatsSupport, U.S. Gov't, P.H.SMaleLosartan/pharmacologyRats, Sprague-DawleySupport, U.S. Gov't, Non-P.H.SAtropine/pharmacology

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Xu, Z., Johnson, A. K.. 1998-10-12. Non-NMDA receptor antagonist-induced drinking in rat. https://ntrs.nasa.gov/citations/20040142188

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