[Effect of central effective substances on alcohol preference].

The alcohol preference has been used as a model of drug habituation in animal experiments in order to examine the influence of altered synaptic efficiency of central transmission systems following acute receptor reactions with agonists or antagonists as well as by alterations of receptor sensitivity in mice. Ethanol in 10 per cent solution as the only beverage over 4 weeks produces an ethanol preference quotient 1 in the free choice of ethanol solution and water. Control animals without ethanol exposure before the preference test are only drinking water and refuse ethanol. A single injection of haloperidol increases the preference, apomorphine as well as a long term haloperidol administration producing a dopaminergic supersensitivity diminishes the preference. Moreover the preference is enhanced by atropine, isoprenaline and pholedrine and is decreased by arecoline, propranolol and phenoxybenzamine. Cyproheptadine and picrotoxine do not influence the preference. The results point to a preference promoting influence of the alpha- and beta-adrenergic transmission and to an inhibition by dopaminergic and cholinergic activity. An influence by the 5-HT and GABA system could not be observed. Additionally the paper describes the decrease of the ethanol preference by the nootropics piracetam, meclofenoxane, methylglucamine orotate and nicergoline.