Effects of perinatal anoxia on the acute locomotor response to repeated amphetamine administration in adult rats.

We examined the possibility that anoxia at birth can alter behavioral sensitization to amphetamine during adulthood. Male rats born either vaginally or by Cesarean section with or without an additional 15-min period of anoxia received five once-daily injections of either d-amphetamine (2.0 mg/kg, i.p.) or vehicle or no pretreatment. One week later, all animals received a challenge injection of amphetamine (0.5 mg/kg, i.p.). The data indicate that all three birth groups of animals pretreated with amphetamine had sensitized equally to the drug's behavioral effect. Of animals pretreated with saline, however, only those born by Cesarean section with added anoxia displayed a sensitized response to amphetamine, suggesting that the stress of daily injection was sufficient to sensitize these animals to amphetamine. These findings provide experimental support for clinical evidence implicating obstetric complications, such as perinatal anoxia, in the pathophysiology of schizophrenia.