Acute renal dysfunction by cadmium injected with cysteine in relation to renal critical concentration of cadmium

In order to study the critical concentration of cadmium (Cd) in acute renal dysfunction following Cd, male mice were injected IV with Cd complexed with cysteine. The critical concentration was 10 micrograms Cd/g wet weight in whole kidney and it was the same as that for Cd-thionein (Cd-Th), which may suggest that the toxicity of Cd-Th is due to Cd ions liberated from Cd-Th in the kidneys. Renal Cd concentration was at first higher than the critical concentration, but decreased to the critical concentration by 24 h after administration. As an index for renal dysfunction, the uptake of p-aminohippurate (PAH) by renal cortical slices in vitro was sensitive, and showed the different time-course from those of urinary protein and glucose levels. The results suggest the usefulness of PAH uptake as an index. Incidental to the renal dysfunction, renal calcium levels exhibited a marked increase.