Influence of lithium and exercise on serum levels of copper and zinc in rats.

The variations in serum levels of Cu and Zn induced by exercise in rats undergoing Li therapy are determined. The results show that exercise until exhaustion leads to a reduction in the Li concentration, which is more pronounced in rats subjected to training (to 50% maximum capacity) in the week before the test. The serum levels of Zn and Cu increased significantly with exhaustion in untrained rats, while there were no significant alterations in trained rats, except for serum Zn in those not treated with Li. The modifications in serum induced by exhaustion are lower in rats treated with Li. It is likely that Li and exercise have opposite effects on the tissue distribution of the two ions studied.