The effect of methylphenidate on overactivity in rats prenatally exposed to alcohol.

Pregnant Long-Evans rats were provided with isocaloric liquid diets containing either ethanol or sucrose, or a standard lab chow diet. Male offspring were utilized to test the effectiveness of methylphenidate in mitigating the overactivity associated with prenatal alcohol exposure. In two experiments, 19 day old rat pups from each prenatal condition were injected with methylphenidate and placed in an open-field. Subjects in the first experiment were injected with 0, 0.5 or 1.0 mg/kg methylphenidate and tested for 5 minutes on each of 3 consecutive days. Drug doses in the second experiment were 0, 2.0 or 8.6 mg/kg and subjects were tested over four days. No evidence was obtained in either experiment that methylphenidate reduced the overactivity of the alcohol-exposed offspring. In fact, in the second experiment, pups exposed to alcohol in utero appeared more sensitive to the stimulating effects of methylphenidate than controls.