Opposite changes in dopamine utilization in the nucleus accumbens and the frontal cortex after electrolytic lesion of the median raphe in the rat

As revealed by the changes in dihydroxyphenylacetic acid (DOPAC) levels and in the DOPAC/Dopamine (DA) ratio, DA utilization was markedly enhanced in the nucleus accumbens and reduced in the prefrontal cortex of rats five days after the electrolytic lesion of the median raphe. These opposite effects were not seen any more seventeen days after the lesion. These results suggest that neurones originating from the median raphe and projecting to the ventral tegmental area exert an opposite effect on the activity of DA cells innervating the nucleus accumbens and on those projecting to the prefrontal cortex.