[Effect of low doses of lead and cadmium on glyoxalase I and glyoxalase II activities of the liver and brain of rats].

The effects of low doses of lead and cadmium on the activities of glyoxalase I and glyoxalase II in liver and brain of male Wistar rats were examined. Generations P, F1 and F2 received lead acetate and cadmium acetate in drinking water. The doses were as follows: group I-Pb 5 ppm, group II-Pb 50 ppm, group III-Cd 0,1 ppm, group IV-Cd 5 ppm. group V-Pb 5 ppm + Cd 0,1 ppm, group VI-Pb 50 ppm--Cd 5 ppm. The control group received sodium acetate with water. P population received Pb and Cd for 40 days before fertilization, and then the pregnant females were given the same doses until the end of pregnancy. Animals of F1 and F2 generation were killed after 30, 60 or 90 days. In liver and brain homogenates the activities of glyoxalase enzyme system were determined by the spectrophotometric method at 240 nm. A little inhibition of glyoxalase I was observed in rats that were given lead for 30 days, while in rats treated for 60 and 90 days the activities of glyoxalase I increased. Glyoxalase II was activated both by lead and cadmium in all groups. In vitro examinations demonstrated that lead and cadmium inhibited the activity of glyoxalase I and activated glyoxalase II.