Antagonists of group I metabotropic glutamate receptors do not inhibit induction of ischemic tolerance in gerbil hippocampus.
In this study we tested the effect of antagonists of two subtypes of the group I metabotropic glutamate receptors (mGluRs GI) on the induction of ischemic tolerance in relation to brain temperature. These experiments were prompted by indications that glutamate receptors may participate in the mechanisms of ischemic preconditioning. The role of NMDA receptors in the induction of ischemic tolerance has been debated while there is lack of information concerning the involvement of mGluRs GI in this phenomenon. The tolerance to injurious 3 min forebrain ischemia in Mongolian gerbils was induced 48 h earlier by 2 min preconditioning ischemia. Brain temperature was measured using telemetry equipment. EMQMCM and MTEP, antagonists of mGluR1 and mGluR5, respectively, were injected i.p. at a dose of 5 mg/kg. They were administered either before preconditioning ischemia in a single dose or after 2 min ischemia three times every 2 h. Both antagonists did not inhibit the induction of ischemic tolerance. Thus, our data indicate that group I metabotropic glutamate receptors do not play an essential role in the induction of ischemic tolerance.
Duszczyk
Malgorzata
M
Department of Neurochemistry, Medical Research Centre, Polish Academy of Sciences, 5 Pawinskiego Street, 02-106 Warsaw, Poland.
Gadamski
Roman
R
Ziembowicz
Apolonia
A
Lazarewicz
Jerzy W
JW
D000818:Animals; D001831:Body Temperature; D002545:Brain Ischemia / Q000209:etiology / Q000473:pathology / Q000517:prevention & control*; D016893:Carotid Stenosis / Q000150:complications; D005849:Gerbillinae; D006624:Hippocampus / Q000187:drug effects / Q000473:pathology*; D019194:Ischemic Preconditioning; D008297:Male; D011725:Pyridines / Q000494:pharmacology; D011804:Quinolines / Q000494:pharmacology; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate / Q000037:antagonists & inhibitors* / Q000502:physiology; D013844:Thiazoles / Q000494:pharmacology
C502015:(3-ethyl-2-methyl-quinolin-6-yl)-(4-methoxycyclohexyl)methanone methanesulfonate; C472365:3-((2-methyl-1,3-thiazol-4-yl)ethynyl)pyridine; D011725:Pyridines; D011804:Quinolines; D064529:Receptor, Metabotropic Glutamate 5; D018094:Receptors, Metabotropic Glutamate; D013844:Thiazoles; C104077:metabotropic glutamate receptor type 1