Cytotoxicity related changes in biochemical cell function following in vitro cadmium treatment

In an effort to examine cellular responses to cadmium insult a bovine kidney cell line was used to monitor select cell functions for toxicity related alterations. Cadmium concentrations used ranged between 0.2 and 2.5 microM CdCl2 and elicited 0-85% cytotoxicity (cell attachment); 24-h incubations were used for all studies. Toxicity related inhibition of leucine incorporation into cellular protein and thymidine incorporation into DNA was noted. Decreases in protein synthesis activity closely paralleled the cytotoxicity profile; DNA synthesis was a less sensitive indicator to toxicity. K+-dependent phosphatase (KP), acid phosphatase (AP) and succinate dehydrogenase (SDH) were monitored in surviving cells and in a cell-free system. Significant inhibitions were detected for all enzyme activities following a 24 h culture with cadmium. KP and AP were most sensitive. In the cell-free system KP was significantly inhibited with 0.1 microM cadmium; AP and SDH were either unchanged or sensitive only at concentrations of 100 microM cadmium or greater. Reduced glutathione (GSH) concentration in surviving cells was elevated up to 7-fold over control cultures. The elevation occurred in a progressive toxicity-related manner.