Prenatal Amphetamine Exposure Effects on Dopaminergic Receptors and Transporter in Postnatal Rats

We investigated the influence of prenatal amphetamine exposure (PAE) on dopamine (DA) receptors, and dopamine transporter (DAT) in various striatal and limbic subregions and locomotor activity induced by novel environmental conditions and amphetamine at two postnatal ages, 35 days old (prepubertal) and 60 days old (postpubertal). Experiments were carried out on pregnant female Sprague-Dawley rats, which were daily injected with either d-amphetamine sulfate (1 mg/kg) or saline solution (0.9%) for 11 days, from gestation day 11-21. In PAE rats compared to control we found the following: at pre-pubertal age, an enhancement of DA D1 in the dorsolateral area of the caudate-putamen (CPu), CPu-ventral and shell of the nucleus accumbens (NAcc) with a decrement of the DA D3 receptors in NAcc, olfactory tubercle (OT), and the islands of Calleja (IoC); whereas at postpubertal age, an increase in the levels of DAT in the NAcc and fundus of the CPu, and OT along with a decrease in the expression of DA D2 receptors only in the NAcc shell were found in PAE rats compared to control. In addition, amphetamine induces a marked decrease in locomotor activity at postpubertal age in rats with PAE. These results suggest a differential effect of amphetamines on the DAT mechanism of the nervous system during embryonic development of animals with implications in behavior and drug addictions at adulthood age.