NIMODIPINE IMPROVES KAINIC ACID-INDUCED NEUROTOXICITY IN CEREBELLAR GRANULAR-CELL CULTURE - A DOUBLE-BLIND DOSE-RESPONSE STUDY

The neuroprotective role of nimodipine was tested in kainic acid (50 a nd 100 mu M) induced neurotoxicity in cerebellar granular cell culture s of 4 to 7 day-old rat pups. Nimodipine was applied in 50, 100 and 20 0 mu M concentrations. Kainate, in either dose, induced cerebellar gra nular cell death in respect to controls and the results were statistic ally significant (P = 0.000 for both doses). However, kainic acid in 1 00 mu M concentration led to higher rates of cell death than 50 mu M ( P = 0.017). The neuroprotective role of nimodipine in kainate induced neurotoxicity was dose dependent. Kainate toxicity in 50 mu M concentr ation was blocked by 50 and 100 mu M nimodipine concentrations (P = 0. 006 and P = 0.002, respectively) while 200 mu M nimodipine was found i neffective. The most effective nimodipine dose for 100 mu M kainic aci d neurotoxicity was 200 mu M (P = 0.000) while 50 and 100 mu M concent rations of nimodipine were found ineffective. In this study, we have p roven the dose-dependent neuroprotective role of nimodipine in kainate induced neurotoxicity in cerebellar granular cell cultures of rat pup s.