Sexually dimorphic influence of prenatal exposure to diazepam on behavioral responses to environmental challenge and on GABA-stimulated chloride uptake in the brain. J Pharmacol Exp Ther

Early developmental exposure to diazepam (DZ) via administra-tion of the drug to the pregnant rat (1.0 or 2.5 mg/kg) over gestational days 1 4 to 20 altered both behavior of adult progeny on two tests of anxiety and function of the benzodiazepine/y-aminobutyric acid (GABA) receptor complex (a neural substrate of anxiety-related behavior) in a sexually dimorphic manner. Adult male rats (60-90 days) exposed in utero to DZ spent significantly more time on the open arm of the elevated plus-maze than male rats exposed to vehicle, whereas plus-maze performance in female rats was unaffected by the early drug exposure. Similarly, early exposure to DZ markedly altered environment-specific social interaction in male rats, leading to increased social inter-action in the unfamiliar environment and decreased social inter-action in the familiar environment. Social interaction in adul