THE INCREASED ETHANOL PREFERENCE IN RATS INDUCED BY CHOICE, DARKNESS,OR DRUGS IS REDUCED BY RITANSERIN

We tested the hypothesis that ritanserin, a serotonin St antagonist, r educes voluntary and induced forms of ethanol drinking. We gave 10 mg/ kg ritanserin IP or SC to groups of rats given either a) a free choice between 3% ethanol and water, or b) kept in the dark for 5 weeks and given a choice between a range of ethanol concentrations (3-25%) and w ater, or c) implanted with osmotic pumps filled with tetrahydro-beta c arboline and given a choice between a range of ethanol concentrations and water. In each case, ritanserin significantly reduced ethanol cons umption and ethanol preference for 8-10 days after the last injection.