Effect of long-term ethanol administration on meprobamate level in brain of rat

Effect of long-term ethanol administration on brain meprobamate concentration (BrMC) was investigated using rats. In ethanol-non-pretreated rats, the average ratio of the maximum BrMC (BrMCmax) to the maximum blood meprobamate concentration (BMCmax) was 0.75 when 25 mg/kg meprobamate were intraperitoneally administered to rats singly or together with ethanol (2 g/kg or 4 g/kg). By a pretreatment of the animals with ethanol at the daily dose of 0.4 g or 0.6 g for 25 days, the average ratio of BrMCmax to BMCmax was 0.91 when the same dose of meprobamate were given into the abdominal cavity. It was considered that by long-term ethanol administration the permeability of blood-brain barrier to meprobamate might be accelerated, resulting in an increase in BrMC.