NBQX REDUCES THRESHOLD OF PROTEIN-SYNTHESIS INHIBITION IN FOCAL ISCHEMIA IN RATS

THE effect of the AMPA antagonist NBQX on peri-infarct inhibition of cerebral protein synthesis (CPS) was studied in rats subjected to 3 h occlusion of the left middle cerebral artery (MCA). Cerebral blood now and CPS were measured with double tracer autoradiography and local ATP content was monitored by bioluminescence imaging. In untreated MCA-occluded animals the perfusion threshold of ATP depletion in cerebral cortex was 17 +/- 5 ml 100 g(-1) min(-1) and that of CPS inhibition was 49 +/- 13 ml 100 g(-1) min(-1). NBQX treatment (2 X 30 mg kg(-1) after vascular occlusion) reduced the perfusion threshold of CPS inhibition to 16 +/- 6 ml 100 g(-1) min(-1) (p < 0.05) whereas that of ATP depletion was not affected (11 +/- 6 mi 100 gl min(-1)). The NBQX-induced pharmacological improvement of peri-infarct CPS is similar to the previously described amelioration of peri-infarct CPS by MK-801 and may contribute to the reduction of infarct size by this treatment.