Sex-dependent maternal deprivation effects on brain monoamine content in adolescent rats

Rats subjected to a single prolonged episode of maternal deprivation (MD) [24h, postnatal days 9-10] show, later in life, behavioural alterations that resemble specific signs of schizophrenia and other neuropsychiatric signs including increased levels of impulsivity and an apparent difficulty to cope with stressful situations. Some of these behavioural modifications are observable in the periadolescent period. However there is no previous information regarding the possible underlying neurochemical correlates at this critical developmental period. In this study we have addressed the effects of MD on the levels of serotonin (5-HT), dopamine (DA) and their respective metabolites in prefrontal cortex, hippocampus, striatum, midbrain and cerebellum of male and female periadolescent Wistar rats. MD rats showed significantly increased levels of 5-HT in all regions studied with the exception of cerebellum. In addition, MD animals showed increased levels of DA in PFC as well as increased levels of DA and a decrease of DOPAC/DA and HVA/DA ratios in striatum. The effect of MD on the monoaminergic systems was in several cases sex-dependent.