title: Protection by NMDA antagonists against selective cell loss following transient ischaemia.
abstract: We have administered antagonists acting competitively or noncompetitively at the N-methyl-D-aspartate receptor after a short period of incomplete ischaemia and evaluated selective neuronal loss in the CA1 region of the rat hippocampus. The competitive antagonists D-(-)-2-amino-7-phosphonoheptanoate (2APH); 100 or 330 mg/kg; 3-(2-carboxypiperazin-4-yl)propyl-1-phosphonate (CPP); 3.3 or 10 mg/kg; and CGS 19755 (cis-4-phosphonomethyl-2-piperidine carboxylate) 3.3 or 10 mg/kg; and the noncompetitive antagonists MK801 [+)5-methyl-10,11-dihydro-5H-dibenzo[a,d]cyclohepten-5,10-imine maleate), 0.3, 1, or 3 mg/kg, and dextrorphan, 2, 6, 18, or 54 mg/kg, were administered intraperitoneally 15 min and 5 h after a 10-min incomplete ischaemia period; additionally MK801 (1 or 3 mg/kg) and CGS 19755 (10 or 30 mg/kg) were administered 5 and 10 h postischaemia. Seven days after ischaemia, the brains were fixed by perfusion. CA1 pyramidal cell counts were performed on Nissl-stained sections using an ocular grid piece. Ventilated (no ischaemia) control animals had a mean of 406 +/- 13 CA1 neurones/3 grid lengths. Ischaemia reduced this mean to 157 +/- 23. A significant protective effect against this cell loss was seen after two injections (at 15 min and 5 h postischaemia) of 2APH, CPP (10 mg/kg), CGS 19755 (10 mg/kg), MK801 (1 mg/kg), and dextrophan (54 mg/kg). Delayed injection (5 and 10 h postischaemia) of CGS 19755 (10 and 30 mg/kg) and MK801 (1 and 3 mg/kg) did not provide any protection against pyramidal cell loss.
authors.affiliation: Department of Neurology, Institute of Psychiatry, London, England.
authors.forename: J H
authors.initials: JH
authors.lastname: Swan
authors.forename: B S
authors.initials: BS
authors.lastname: Meldrum
mesh_terms: D015763:2-Amino-5-phosphonovalerate / Q000031:analogs & derivatives*; D000596:Amino Acids / Q000494:pharmacology; D000818:Animals; D000927:Anticonvulsants / Q000378:metabolism / Q000494:pharmacology; D001224:Aspartic Acid / Q000031:analogs & derivatives* / Q000037:antagonists & inhibitors / Q000378:metabolism; D001921:Brain / Q000473:pathology; D002545:Brain Ischemia / Q000378:metabolism*; D003986:Dibenzocycloheptenes / Q000494:pharmacology; D016291:Dizocilpine Maleate; D008297:Male; D016202:N-Methylaspartate; D009474:Neurons / Q000473:pathology; D010875:Pipecolic Acids; D010879:Piperazines / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D011919:Rats, Inbred Strains; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter / Q000187:drug effects / Q000378:metabolism
chemical_list: D000596:Amino Acids; D000927:Anticonvulsants; D003986:Dibenzocycloheptenes; D010875:Pipecolic Acids; D010879:Piperazines; D010880:Piperidines; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D001224:Aspartic Acid; C053672:selfotel; D016202:N-Methylaspartate; D016291:Dizocilpine Maleate; D015763:2-Amino-5-phosphonovalerate; C050592:3-(2-carboxypiperazin-4-yl)propyl-1-phosphonic acid; C031231:2-amino-7-phosphonoheptanoic acid