Distribution of cadmium in body organs and hepatic metallothionein content following chelation therapy.

1. Calcium trisodium diethylene triamine penta-acetate (CaNa3DTPA), sodium 1,2 diaminocyclohexane tetra-acetate (Na2CDTA), triethylenetetramine hydrochloride (TETA.HCl) and sodium diethyldithiocarbamate (NaDDC) were investigated for their efficacy to mobilize cadmium (Cd) from various tissues and hepatic metallothionein (MT) in Cd-exposed rats. 2. All chelating agents reduced the hepatic Cd burden but did not elicit any influence on other tissues, except that TETA.HCl lowered pancreas Cd and NaDDC increased brain Cd. 3. Cadmium-induced hepatic MT was lowered upon treatment with CaNa3DTPA while it increased further following treatment with NaDDC. 4. The chelating agents, in split doses, are capable of reducing the hepatic burden of Cd and altering the hepatic MT level. 5. While all the chelating agents decreased Cu content of hepatic MT, only CaNa3DTPA decreased its Zn content and TETA.HCl mobilized MT-bound Cd. 6. The administration of chelating agents alone in normal animals showed that NaDDC induced greater hepatic MT synthesis and increased MT-bound Zn than other chelating agents.