Differential pharmacological responses to ethanol, pentobarbital and morphine in rats selectively bred for ethanol sensitivity.

The hypothermic and analgesic effects of ethanol, pentobarbital and morphine were examined in two lines of rats that had been selectively bred for their differential sensitivity to ethanol. Males and females of the least-affected (LA) line were observed to be less sensitive than their most-affected (MA) counterparts to hypothermia and analgesia induced by ethanol and morphine. By contrast, no differences were observed with respect to pentobarbital-induced hypothermia. At the dose used, pentobarbital had no significant analgesic effect in either animal line.