KETAMINE AND NIFEDIPINE PKOTECT CULTUKED CORTICAL NEUKONS AGAINST INJURIOUS EFFECT OF GTUTAMATE

The effects ofglutamate on cultured cortical neurons and the protective effect ofketamine and nifedipine were studied.On day 10 after plating of the cortical cells from 16～18 day-old fetal rats,the cultures were exposed to 50μmol·L^-1 glutamate and low glucose(1g·L^-1)for 10min～24 h.The results showed that a release of lactate dehydrogenase(LDH)into the culturesupernatant was observed as a function of time.The values of LDH efflux in culture medium wassignificantly lower than those of controls when the cells were pretreated with ketamine or nifedipine 10min prior to addition of glutamate.More significant decrease of LDH activity in culture medium wasobserved when the two drugs were used in combination. These results demonstrate that the dissociatedcuItured cort ical neurons from fetal rat are seriously damaged by glutamate.Such damage could beattenuated by ketamine and nifedipine,suggesting that ketamine and nifedipine may protect neuronsfrom the glutamate toxicity,and the effect of combining ketamine and nifedipine was greater thaneither ketamine or nifedipine alone.