EFFECTS OF THE CALCIUM-CHANNEL ANTAGONIST DARODIPINE ON ETHANOL WITHDRAWAL IN RATS

The effect of the dihydropyridine calcium channel antagonist, darodipi ne, on ethanol withdrawal syndrome was examined in rats made dependent on ethanol by repeated ethanol administration for six consecutive day s. Chronic co-administration of darodipine prevented the severity of e thanol withdrawal signs in a dose-dependent fashion. By contrast, acut e administration of darodipine during the ethanol withdrawal phase was ineffective in reversing the withdrawal symptoms. The results suggest that the presence of darodipine in the central nervous system during the adaptative responses to ethanol is necessary to reduce the severit y of the withdrawal syndrome. They also provide further evidence for a potential clinical usefulness of dihydropyridine calcium channel bloc kers in treatment of ethanol withdrawal.