摘要：Environmental toxicology of metals, like that of other chemicals, consists of ecotoxicology and biotoxicology. Among the biotoxicology, pathophysiological approach, along with toxicological approach, is of particular importance for understanding effects of metals on human health and establishing measures to cope with them including biological monitoring and development of exposure parameters and preventive methods. Experiments have been carride out on chemical biology of chromium and clinical biochemistry of organic tin compounds. The aim of these studies is to demonstrate and evaluate the pathophysiological approach in the study of metal toxicity. Recent results in our laboratory are as follows. 1. Chemical toxicology of chromium. Two low-molecular-weight chromium-binding substances, LMCrI and II, were purified from the liver of dogs. Chromium bound to them showed a lower acute toxicity and higher rates of urinary excretion and renal clearance than potassium dichromate (VI) and chromium (III) chloride. The results together with other findings indicate that LMCrs play an important role in the detoxification and excretion of chromium in mammals. They also show that chemical form of metals and binding protein in the body are important factors in metal toxicity. 2. Clinical biochemistry of organic tin compounds Triphenyltin and tributyltin have been shown to inhibit insulin release from pancreatic islets, subsequently inducing diabetic lipemia due to insulin deficiency. The organic tins also inhibited collagen-induced aggregation and ATP secretion of platelets. Furthermore, they showed a dosedependent inhibition of O2- production, O2 consumption and degranulation of leukocytes. These results indicate that organic tins affect a common mechanism of the stumulus-response coupling in the cell membrane.
关键词：metal toxicity;pathophysiology;biotoxicology;chromium;low-molecular curomium-binding substance;organic tin compound;diabetic lipemia;platelet aggregation;stimulus-response coupling
