Primary Study on the Effects of Environmental Pollutants on Brain and Circulating System and on the Biological Kinetics (Especially the Effects of Heavy Metals, Cadmium and Vanadium)

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Effects of environmental pollutants, especially cadmium (Cd) and vanadium (V) on rat brain and circulating system, biological kinetics of these heavy metals in vivo and in vitro, and then environmental contaminations by heavy metals containing Cd and V from distributions of these metals in wild birds were investigated in the present study.(1) Analytical methods for heavy metal contents in biological samples : Atomic absorption spectrophotometry and inductively coupled plasma - atomic emission spectrometry were used for determination of Cd content and other heavy metal contents containing V content, respectively.(2) Cd infusion and Cd uptake : Rats were contineously infused i.v. with CdCl_2 after anaethesia and cannulations. Plasma Cd level was tolerably constant 30 min after infusion (approx.3ppm). After 2hr infusion, EDTA washout decreaseed Cd levels in brain and vessels. However, predicted washout effects could not be obtained in other tissues containing liver. These results were not … More compatible in part with the results of Cd uptake of liver and brain in vitro. These require further study.(3) V uptake in vitro : Uptake of V in tissue level was investigated and the results suggested that 2 compartments showing low and high affinities existed as V fractions. Intracellular V content was approx. 10% and other V was thought to be presented in extracellular space. The result suggested that contractile phenomena could not be explained by inhibitory effects by cellular V on various ATPase and other effects by cellular V.(4) Effects of one of V compounds, vanadate on the response of stimulated nerve via intestinal wall and the Ca^<2+>-induced contractions in beta-escin or TritonX-100 treated skinned muscles were investigated. VAN enhanced the responses of nerve stimulated muscles and slinned muscles. Then, it was sugessted that when VAN entered into cell, V inhibits contractile protein system. Mechanism for these effects will be needed further study.(5) The contaminations by heavy metals containing Cd and V in wild geese were investigated. Cd contents in geese livers and kidneys were higher than those of 10 years old human. Further, Cd contents in flat bone were less than that of long bone. On the other hand, extremely strong correlations among Cd, Cr, Ti, and Li were obtained in livers and kidneys from approx. 50 wild birds. These results suggest that wild birds have been contaminated by these heavy metals. Less