Participation of the cholinergic system in ameliorating effect of vasopressin fragment by group I metabotropic glutamate-receptor blockade.
The effect of [pGlu4,Cyt6,Arg8]-vasopressin fragment 4-9 (AVP4-9) on group I metabotropic glutamate (mGlu1) receptor antagonist-induced memory deficits was studied using 8-arm radial maze performance with 4 arms baited. In addition, the participation of the cholinergic system in the ameliorating effect of AVP4-9 on mGlu1 receptor antagonist-induced memory deficits was also investigated. Intrahippocampal injection of (R,S)-1-aminoindan-1,5-dicarboxylic acid (AIDA), an mGlu1-receptor antagonist, significantly increased total error, reference memory error, and working memory error at a dose of 20 nmol/side. AVP4-9 (0.1 and 1.0 microg/kg, s.c.) showed a significant ameliorative effect on AIDA-induced memory deficits. Improvement of AIDA-induced memory deficit in response to AVP4-9 treatment was significantly antagonized by scopolamine (5 nmol/side) but not by mecamylamine (200 nmol/side) at a dose that caused no effect on performance when injected separately. These findings indicate that the ameliorating effect of AVP4-9 on AIDA-induced memory deficit may be closely associated with the muscarinic receptor.
Tarumi
Tadatsugu
T
Department of Medical Pharmacology, Okayama University Graduate School of Medicine, Dentistry and Pharmaceutical Sciences, Okayama, Japan.
Mikami
Azusa
A
Shimada
Kenichi
K
Kamei
Chiaki
C
D000818:Animals; D001127:Arginine Vasopressin / Q000031:analogs & derivatives* / Q000378:metabolism; D001522:Behavior, Animal / Q000187:drug effects*; D002799:Cholinergic Fibers / Q000187:drug effects* / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology*; D006624:Hippocampus / Q000187:drug effects* / Q000378:metabolism; D007189:Indans / Q000494:pharmacology*; D008297:Male; D018782:Maze Learning / Q000187:drug effects; D008464:Mecamylamine / Q000494:pharmacology; D008568:Memory / Q000187:drug effects*; D018727:Muscarinic Antagonists / Q000494:pharmacology; D018733:Nicotinic Antagonists / Q000494:pharmacology; D010446:Peptide Fragments / Q000378:metabolism*; D011761:Pyrrolidonecarboxylic Acid / Q000031:analogs & derivatives* / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D018094:Receptors, Metabotropic Glutamate / Q000037:antagonists & inhibitors* / Q000378:metabolism; D011976:Receptors, Muscarinic / Q000187:drug effects / Q000378:metabolism; D012601:Scopolamine / Q000494:pharmacology
C095756:1-aminoindan-1,5-dicarboxylic acid; D018691:Excitatory Amino Acid Antagonists; D007189:Indans; D018727:Muscarinic Antagonists; D018733:Nicotinic Antagonists; D010446:Peptide Fragments; D018094:Receptors, Metabotropic Glutamate; D011976:Receptors, Muscarinic; C104077:metabotropic glutamate receptor type 1; D001127:Arginine Vasopressin; D008464:Mecamylamine; C052436:argipressin (4-9), (3-1')-disulfide Cys(6)-; D012601:Scopolamine; D011761:Pyrrolidonecarboxylic Acid