Norbinaltorphimine protection against N-methyl-D-aspartic acid-induced convulsions and mortality.
The kappa-selective opioid antagonist, norbinaltorphimine (Nor-BNI), was tested against convulsions and mortality induced by the excitatory amino acids, N-methyl-D-aspartic acid (NMDA), (R,S)-alpha-amino-3- hydroxy-5-methyl-4-isoxazole propionate (AMPA) and kainic acid and the gamma-aminobutyric acid antagonist, bicuculline. Nor-BNI (10-40 nmol; intracerebroventricularly, i.c.v.) protected against NMDA (0.5-2.0 nmol i.c.v.)-induced convulsions and NMDA (2 nmol i.c.v.) and AMPA (2 nmol i.c.v.)-induced mortality. The opioid antagonist, naloxone (10 nmol i.c.v.), had no protecting activity. In vitro, Nor-BNI competed with the binding of the specific NMDA receptor ligand, [3H]D,L-(E)-2-amino-4-propyl- 5-phosphono-3-pentenoic acid ([3H]CGP 39653, 10 nM; IC50 of 1.63 +/- 0.20 microM) to mouse brain membrane preparations. The results indicate that the protecting activities of Nor-BNI are mediated by NMDA receptor-related mechanisms.
Shukla
V K
VK
Department of Pharmacology, Faculty of Medicine, University of Ottawa, Ontario, Canada.
Lemaire
S
S
D015763:2-Amino-5-phosphonovalerate / Q000031:analogs & derivatives / Q000378:metabolism; D000818:Animals; D001640:Bicuculline / Q000633:toxicity; D001667:Binding, Competitive / Q000187:drug effects; D001921:Brain / Q000187:drug effects / Q000378:metabolism; D007051:Ibotenic Acid / Q000031:analogs & derivatives / Q000633:toxicity; D007276:Injections, Intraventricular; D007608:Kainic Acid / Q000633:toxicity; D008297:Male; D051379:Mice; D016202:N-Methylaspartate / Q000037:antagonists & inhibitors* / Q000633:toxicity; D009271:Naltrexone / Q000031:analogs & derivatives* / Q000494:pharmacology; D016194:Receptors, N-Methyl-D-Aspartate / Q000037:antagonists & inhibitors; D012640:Seizures / Q000139:chemically induced / Q000401:mortality / Q000517:prevention & control*; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid
D016194:Receptors, N-Methyl-D-Aspartate; C069052:CGP 39653; D007051:Ibotenic Acid; C051844:norbinaltorphimine; D009271:Naltrexone; D016202:N-Methylaspartate; D015763:2-Amino-5-phosphonovalerate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D007608:Kainic Acid; D001640:Bicuculline