Jm. Luque et al., Glutamate N-methyl-D-aspartate receptor blockade prevents induction of GAP-43 after focal ischemia in rats, NEUROSCI L, 305(2), 2001, pp. 87-90
Growth associated protein-43 (GAP-43) gene induction may be involved in rea
ctive events that follow cerebral ischemic damage. Antagonists of the N-met
hyl-D-aspartate (NMDA) subclass of glutamate receptors are thought to ameli
orate functional outcome after ischemic injury. To assess whether glutamate
NMDA receptor blockade could alter GAP-43 postischemic induction we perfor
med immunocytochemistry in rat brains that had been subjected to middle cer
ebral artery occlusion. Cortical cells did not constitutively express GAP-4
3, yet focal ischemia induced its expression, with an intense signal genera
ted in cells over the lesioned area at 6 h, increasing at 24 h postischemia
. This signal was effectively decreased by pretreatment with the NM DA rece
ptor antagonist (5R,10S)-(+)-5-methyl-10,11-dihydro-5H-dibenzo[a,d]-cyclohe
pten-5,10-imine hydrogen maleate (0.1 mg/kg s.c.), but not by the glutamate
release blocker riluzole (8 mg/kg i.v.), suggesting that overactivation of
NM DA receptor during ischemia is linked to GAP-43 expression. (C) 2001 El
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