The effect of sodium thiosulfate on subcellular localization of platinum in rat kidney after treatment with cisplatin.

Female Sprague-Dawley rats were given 10 mg/kg of i.v. cis-diammine-dichloroplatinum(II) (cisplatin) simultaneously with i.v. sodium thiosulfate (STS) at a 200-fold molar excess to cisplatin, then subcellular (nuclei, mitochondria, microsomes, cytosol) distribution of platinum within rat kidney cells was determined 15 min, 1 h, 8 h and 24 h after cisplatin injection. Blood urea nitrogen levels were measured in rats treated in the same manner described above. STS was found to block cisplatin-induced nephrotoxicity. However, differences in platinum concentrations in total homogenate or each subcellular fraction between STS-treated rats and controls were not significant enough to fully account for the drastic protective effect of STS against cisplatin nephrotoxicity.