Brain N-acetyl aspartate concentrations measured by H-1 MRS are reduced inadult male rats subjected to perinatal stress: preliminary observations and hypothetical implications for neurodevelopmental disorders

The present study was undertaken to determine if the concentration of brain N-acetyl-aspartate (NAA), a putative neuronal marker, is reduced in adult rats subjected to stress during the perinatal period. As the prenatal stres sor, pregnant rats were subjected to restraint stress for one hour twice da ily from days 14-21 of gestation; stressed offspring were reared by normal darns and studied as adults. As the postnatal stressor, normal pups were re ared by prenatally 'stressed' dams and studied as adults. As compared to no n-stressed controls (n=6), NAA concentrations were significantly reduced 21 and 25% in left frontal cortex from the prenatal (n=4) and postnatal (n=6) stress groups, respectively. The data suggest that in perinatally stressed adult offspring permanent neuronal damage or loss has occurred. While no d irect causal associations between perinatal stress and the developmental of particular disorders can be inferred from these limited data, the effects of perinatal stress on subsequent brain neuropathology are reviewed, partic ularly in relation to NAA. For hypothesis-generating purposes, the possible relevance of stress and NAA to the neurodevelopmental hypothesis of schizo phrenia is discussed in greater detail. (C) 1999 Elsevier Science Ltd. All rights reserved.