Abstract
The effects of ethanol on the contents of norepinephrine (NE) and dopamine (DA) and the activities of related enzymes in the various regions of rat brains with different doses and mode of administration of ethanol were investigated. In acute ethanol intoxication, steady-state levels of NE were not altered. Continuous ethanol intoxication, however, significantly reduced NE contents and tended to decrease the activity of dopamine-β-hydroxylase in the hippocampus. The decrease in NE contents became more significant during ethanol withdrawal, especially in the medulla oblongata and the striatum. DA contents were increased in the brain-stem region in all ethanol-treated rats. The increase in DA contents correlated with the increase in tyrosine hydroxylase activity. The present data suggest that the dopaminergic system may contribute to the development of physical dependence on ethanol.
