Ethanol withdrawal in mice bred to be genetically prone or resistant to ethanol withdrawal seizures

We are engaged in a selective breeding program developing lines of mice which differ in severity of withdrawal convulsions after ethanol treatment. Withdrawal seizure prone (WSP) mice show greater handling-induced convulsion scores than withdrawal seizure resistant (WSR) mice after 3 days of ethanol intoxication. In the present experiments, we sought to characterize these mice further as a model of genetic susceptibility to ethanol dependence and withdrawal. During withdrawal after chronic treatment with ethanol, WSP mice displayed more severe handling-induced convulsions and tremor than WSR mice, and tended to show greater reduction of exploratory activity. WSP and WSR mice did not differ in ethanol metabolism after acute treatment with ethanol alone or after chronic treatment with ethanol and pyrazole, an alcohol dehydrogenase inhibitor. Six to 10 hr after an acute injection of ethanol, WSP and WSR mice showed elevated handling-induced convulsions. This elevation was more pronounced in WSP mice than in WSR mice. WSP mice also showed slightly more severe convulsions than WSR mice when treated with saline or pyrazole alone. In summary, WSP and WSR mice treated with identical doses of ethanol differ in several symptoms of withdrawal, whereas not differing in ethanol metabolism. These mice constitute a useful population in which to study the molecular mechanisms of ethanol dependence and withdrawal.