[Effect of prenatal administration of diazepam and buspirone on brain monoamines and avoidance learning behavior in offspring rats in relation to the influence of maternal stress caused by subcutaneous injection].

The dams of each group of rats were given subcutaneous injections of diazepam (5 mg/kg), buspirone (10 mg/kg) or saline day 7 to 21 of their gestation periods. The intact group that received no injection was compared with the injection groups to evaluate the effects of stress caused by the subcutaneous injections. The brain concentrations of monoamines were investigated in 1-day-old female rats. Levels of tryptophan, 5-HT, 5-HIAA and 3-o-MDOPA decreased, but DOPAC increased in the saline group in comparison with the intact group. Tryptophan, 5-HT, 5-HIAA and 3-o-MDOPA increased in the diazepam group in comparison with the saline group. Tryptophan increased, and DOPAC, HVA and MHPG decreased in the buspirone group in comparison with the saline group. The avoidance learning test in a shuttle box was applied to 9-week-old offspring male rats. The saline group learning score had the poorest among the four groups. These results suggest that the prenatal stress of hypodermic injections may adversely affect the learning ability in the offspring. The two antianxiety drugs may overcome these adverse effects through reduction of prenatal stress.