Behavioural effects of prenatal diazepam administration on anxiety patterns in rats.

Diazepam (10 mg/kg, ip) treatment was given from day 13 to 20 of gestation to pregnant rats, this being the critical period for neural development in this species. The pups born were subjected to open-field exploratory behaviour, tunnel-board exploratory behaviour, elevated zero maze behaviour and social interaction tests at 8-9 weeks of age. The results indicate that prenatal diazepam treatment induces a significant increase in open-field ambulation, grooming, scratching and licking/washing, whereas rearing and faecal dropping remain unchanged. Significant reduction in tunnel-board exploratory activity, activity on zero-maze and social interaction were also observed in the prenatally diazepam treated offsprings. The results suggests that prenatal interference in the form of diazepam leaves a lasting imprint on offsprings resulting in hyper-emotional responsiveness and anxiety state.