Comparative effects of chelating drugs on trace metal and biochemical alterations in the rat.

Abstract

Chelation therapy is the most successful modality for the management of heavy metal poisoning. The success of these drugs stem from their multidentate polyfunctional chelating behavior. The therapeutic mechanism for chelating drugs involves their interaction with toxic metals leading to their rapid excretion from the body. However, because of their indiscriminate affinity for various metal ions, the potential interactions between these drugs and endogenous trace metals is of concern. It was, therefore, of importance to define new chelating drugs which in addition to being effective as an antidote in metal poisoning may possess low undesirable toxicity. In the present communication the authors compare the acute effect of Cyclam with those of other conventional chelating drugs namely, triethylenetetramine (TETA), reduced glutathione (GSH), ethylenediamine tetraacetic acid (EDTA), cyclohexanediamine tetraacetic acid (CDTA), diethylene triamine pentaacetic acid (DTPA) and hydroxyethylenediamine triacetic acid (HEDTA) on (i) serum levels of Cu, Zn, lactate dehydrogenase (LDH), glutamyloxaloacetic transaminase (GOT) and ceruloplasmin (CP); (ii) hepatic and renal levels of Cu, Mn, Zn and Fe and (iii) hepatic and renal levels of GSH, glutathione-S-transferase (GST) and phosphoglucomutase (PGM) at various time intervals (16, 24 and 72 hrs) after their administration to rats.