Prenatal stress impairs maternal behavior in a conflict situation and reduces hippocampal benzodiazepine receptors.

Maternal behavior (pup retrieval) was assessed in prenatally stressed rats during control and conflict situations (having to pass through an airstream) when their pups were 4-5 days old. There was no difference in pup retrieval between experimental and control rats under normal conditions but only 52% of the former retrieved their pups during the conflict situation, compared with 96% of the controls. Catecholamine (CA) levels in the arcuate nucleus (Arc.n.) and noradrenaline in the medial preoptic nucleus (POM) were not altered in prenatally stressed females, but their dopamine levels in the POM tended to be lower (p less than 0.1). The number of benzodiazepine (BZ) receptors in the hippocampi of prenatally stressed females was significantly lower than in controls. We conclude from these results that random prenatal noise and light stress increases the vulnerability to stressful situations in the female offspring during adulthood, which may be accompanied by altered CA function in the hypothalamus and BZ binding in the hippocampus.