Prenatal Ethanol Exposure Affects Temperature Responses of Adult Rats to Pentobarbital and Diazepam Alone and in Combination with Ethanol

Long-term effects of prenatal alcohol exposure on body temperature responses to pentobarbital and diazepam and to either drug in combination with ethanol were studied in adult rats who were the offspring of dams fed a 5.0% w/v ethanol-containing liquid diet during the last 2 weeks of gestation. Adult offspring of pair-fed and chow-fed dams served as nutritional and normal controls, respectively. Pentobarbital (6.25–25.0 mg/kg) and diazepam (2.5–10.0 mg/kg) produced significantly greater dose-related hypothermic responses in females than males. Following either pentobarbital or diazepam administration female prenatally ethanol-exposed (E) rats responded with a greater fall in body temperature than the controls. Significantly greater hypothermia occurred in both male and female E rats than in controls when ethanol (1.5 g/kg) was administered together with pentobarbital or diazepam. However, the drug combinations did not produce additive effects on body temperature in any prenatal treatment group. Pentobarbital produced acute cross-tolerance to ethanol while diazepam potentiated ethanol's effect. These studies confirm and extend our previous findings of enhanced hypothermic responses to ethanol in adult rats exposed to ethanol in utero and indicate that maternal alcohol consumption produces long-term effects on the central thermoregulatory systems of offspring.