Activity of the enzymes dopamine-beta-hydroxylase and phenylethanolamine-N-methyltransferase in discrete brain regions of the copper-zinc deficient rat following aluminum ingestion.

We have investigated the possible interactions between the dietary intake of copper, zinc, or aluminum and the activities of the enzymes dopamine-beta-hydroxylase (DBH, EC.1.14.2.1) and phenylethanolamine-N-methyltransferase (PNMT, EC.2.1.1.28) in the male rat brain. Exposure to aluminum was for 120 days at 1000 ppm. The results showed that a diet suboptimal in copper or zinc decreased the activity of both enzymes in the three brain regions studied, including the frontal cortex, hippocampus, and cerebellum. The addition of aluminum to the suboptimal zinc diet restored the activity of both enzymes to within range of control values. The data are discussed with respect to an interaction between zinc and aluminum.