Postnatal Ontogeny of Rat Brain D2 Dopamine in a Prenatal Stress Model

V. G. BARROS; L. A. BOADO; M. C. ANTONELLI

Orlando, Florida

Congreso; XII Reunión Anual de la Society for Neurosciencie; 2002

Society for Neuroscience

Formation of forebrain dopamine projections is highly vulnerable to insults inflicted during the perinatal period. We have previously demonstrated that restraint prenatal stress inflicted during the last week of pregnancy increased D2-type dopamine (DA) receptors levels in brain limbic areas of rat adult offsprings. Employing the same restraint stress model to the pregnant dam, we have studied the levels of dopamine receptors by quantitative autoradiography in the offspring brains at postnatal day (PND) 21, 28, 45 and 60. The results obtained showed that no differences were found in D2 receptor levels at PND 21 and 28 between control and prenatally stressed rats in dorsal frontal cortex (DFC) and hippocampus (HIP). After PND 45, DA receptor levels showed a similar increase in DFC and HIP as previously found in adult offsprings (PND 90). These results show that changes in dopamine receptors in prenatally stressed rats are only observed after puberty. This evidence is an indication that the effect of prenatal stress is not directly acting on the developing dopamine receptors. Alternatively, our observations may suggest that the insult received prenatally is modifying the sensitivity of the receptors to the modulation of sex steroids during puberty.