Summary.

The effect of the dihydropyridine calcium channel blocker nifedipine on ethanol withdrawal symptoms and the activity of neuronal nitric oxide synthase (nNOS) was investigated in rats made dependent on ethanol by repeated ethanol administration for eight consecutive days. Forty eight hours after the last administration, behavioral changes were evaluated and the withdrawal symptoms were observed. Co-administration of nifedipine attenuates these symptoms, which correlate with the biochemical assay of nNOS. The data on the nNOS activity showed that ethanol, administered alone, significantly increased by 74% nNOS activity. Nifedipine itself did not change the enzyme activity, while in the combination group nifedipine decreased the brain nNOS activity, induced by multiple ethanol administration. The results of our study suggest that nifedipine may play an important role in reduction the severity of the withdrawal symptoms and related to it changes in nNOS.