Although appearing robust at birth on gross observation, more subtle measurements revealed that rat pups born by C-section show altered respiratory rates and activity levels and increased levels of whole brain lactate, suggestive of low grade brain hypoxia, during the first 24 h of life, in comparison to vaginally born controls. Pups born by C-section with 15 min of added acute anoxia were pale, hypotonic, and inactive at birth and showed reduced respiration and high brain lactate levels. However, these alterations resolved by 1-5 h after birth and, with few exceptions, animals in the anoxic group remained normal with respect to these parameters during the remainder of the first 24 h of life. These findings highlight the sensitivity of DA pathways to variations in birth procedure and support the notion that birth complications might contribute to the pathophysiology of disorders involving central dopaminergic neurons, such as schizophrenia. Caesarean section birth with general anesthesia increases dopamine-mediated behavior in the adult rat.
Schizophrenia is associated with both increased dopaminergic activity and perinatal complications.
For comparison with our previous results, we also included rats born by C-section from decapitated dams. Birth insult increases amphetamine-induced behavioral responses in the adult rat. In addition, adult rats that had been born by Caesarean section, either with or without acute global anoxia, showed markedly greater dopamine release from the nucleus accumbens in response to repeated stress, in comparison to vaginally born controls. The aim of the present study was to test whether these birth complications also result in long-term changes in behavior mediated by dopamine systems. Behavioral responses were further analysed from video recordings of the animals' behavior.