Transport of inorganic phosphate in renal cortical brush-border membrane vesicles of cadmium-intoxicated rats.
The effect of cadmium intoxication on the renal proximal tubular phosphate transport system was studied in adult male Sprague-Dawley rats. Subcutaneous injections of CdCl2 at a dose of 2 mg Cd/kg body wt per day for 2 weeks induced marked polyuria, glycosuria, proteinuria, and phosphaturia, which are characteristics of chronic cadmium intoxication. In the renal cortical brush-border membrane vesicles prepared from cadmium-intoxicated rats, the cadmium content was drastically increased and the Na(+)-dependent phosphate uptake was markedly attenuated. Similar results were obtained in normal membrane vesicles directly exposed to free cadmium. These results indicate that cadmium intoxication impairs the Na(+)-phosphate cotransport system in the proximal tubular brush-border membrane, which may lead to phosphaturia in intact animals.
Ahn
D W
DW
Department of Physiology, Kosin Medical College, Pusan, Korea.
Park
Y S
YS
D000818:Animals; D001693:Biological Transport, Active / Q000187:drug effects; D002104:Cadmium / Q000008:administration & dosage / Q000378:metabolism / Q000633:toxicity*; D019256:Cadmium Chloride; D002273:Carcinogens / Q000633:toxicity*; D002712:Chlorides / Q000008:administration & dosage / Q000378:metabolism / Q000633:toxicity*; D004231:Diuresis / Q000187:drug effects; D007672:Kidney Cortex / Q000187:drug effects* / Q000378:metabolism / Q000648:ultrastructure; D007677:Kidney Function Tests; D008297:Male; D008871:Microvilli / Q000187:drug effects / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism*; D051381:Rats; D017207:Rats, Sprague-Dawley; D012964:Sodium / Q000378:metabolism / Q000494:pharmacology
D002273:Carcinogens; D002712:Chlorides; D010710:Phosphates; D002104:Cadmium; D012964:Sodium; D019256:Cadmium Chloride