Centrally administered vasopressin antagonizes pentobarbital-induced narcosis and depression of hippocampal cholinergic activity.
Intracerebroventricular (ICV) microinjection of arginine vasopressin (AVP) to pentobarbital-anesthetized rats produced shortening of the duration of narcosis. This analeptic effect was blocked by atropine, indicating the central cholinergic nature of the response. AVP also increased hippocampal sodium-dependent high affinity choline uptake activity that had been depressed by the barbiturate. The AVP analeptic effect was blocked by pretreatment with a V-1 (vasopressor), but not a V-2 (antidiuretic), vasopressin receptor antagonist. These results suggest that ICV AVP produces its analeptic effect by interacting with central V-1 receptors to activate a hippocampal cholinergic arousal system. The cholinergic arousal effect may be a factor in the memory enhancing property of AVP.
Horita
A
A
Department of Pharmacology, University of Washington School of Medicine, Seattle 98195.
Carino
M A
MA
D000109:Acetylcholine / Q000502:physiology; D000818:Animals; D001127:Arginine Vasopressin / Q000008:administration & dosage / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D001143:Arousal / Q000187:drug effects; D001285:Atropine / Q000494:pharmacology; D000697:Central Nervous System Stimulants / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D007276:Injections, Intraventricular; D008297:Male; D008568:Memory / Q000187:drug effects; D008845:Microinjections; D010424:Pentobarbital / Q000037:antagonists & inhibitors*; D051381:Rats; D011919:Rats, Inbred Strains; D011945:Receptors, Angiotensin / Q000187:drug effects* / Q000502:physiology; D017483:Receptors, Vasopressin
D000697:Central Nervous System Stimulants; D011945:Receptors, Angiotensin; D017483:Receptors, Vasopressin; D001127:Arginine Vasopressin; D001285:Atropine; D010424:Pentobarbital; D000109:Acetylcholine