Cadmium accumulation and subcellular distribution in relation to cadmium chloride induced cytotoxicity in vitro.
A bovine kidney cell culture system was used to assess what relationship cadmium (Cd) uptake and subcellular distribution had to cadmium chloride induced cytotoxicity. Twenty-four hour incubation with 0.1-10 microM Cd elicited 0-90% cytotoxicity. Fifty percent cytotoxicity was estimated to result from 0.8 microM Cd. A concentration-related Cd accumulation paralleled the cytotoxicity profile. The time-course for Cd accumulation was linear for the first 6 h of exposure and plateaued by 18 h post-exposure. When the degree of cytotoxicity was compared with the cellular Cd burden at 24 h post-treatment a least-squares linear regression analysis (r = 0.93) indicated a direct relationship. Subcellular distribution studies indicated greater than 90% Cd recovery from the soluble supernatant (105 000 g) at all levels of cytotoxicity studied. Metallothionein sequestered less than 25% of the cellular Cd. As a result of the correlation of the degree of cytotoxicity with the cellular Cd burden and the independence of subcellular distribution from cytotoxicity, a cumulative mechanism of toxicity for Cd in MDBK cells was suggested.
D000818:Animals; D002104:Cadmium / Q000378:metabolism* / Q000633:toxicity; D019256:Cadmium Chloride; D002417:Cattle; D002470:Cell Survival / Q000187:drug effects; D002478:Cells, Cultured; D003600:Cytosol / Q000378:metabolism; D007668:Kidney / Q000378:metabolism / Q000648:ultrastructure; D008668:Metallothionein / Q000378:metabolism
D002104:Cadmium; D008668:Metallothionein; D019256:Cadmium Chloride