Behavioral effects of ethanol and salsolinol in mice selectively bred for acute sensitivity to ethanol

The effects of intracerebral injection of salsolinol, the condensation product of dopamine and acetaldehyde, were compared in LS and SS mice selectively bred for differential sleep time following an intraperitoneal injection of ethanol. Salsolinol differentially affected open-field activity in the two mouse lines. Low doses of salsolinol increased open-field activity in the SS line; no such effects were obtained in the LS line. Larger doses decreased activity in both lines but the LS mice were more sensitive to this effect. Similar effects on open-field activity have been reported for ethanol in these same lines of mice. A 40 micrograms dose of salsolinol increased ethanol-induced sleep time in both lines but the increase was greater in the LS line. With lower doses of salsolinol the duration of ethanol-induced sleep time decreased in SS mice and increased in LS mice. This effect of salsolinol on sleep time most likely involves some CNS mechanism since salsolinol did not alter ethanol elimination rate in the two lines of mice. A more severe and prolonged hypothermia developed in LS mice following injections of salsolinol or equal doses of ethanol; however, equi-hypnotic doses of ethanol elicited similar hypothermic responses. Taken together, these data support a possible role for salsolinol in ethanol's actions.