The effects of CuSO4 and pH on Ca2 + transmembrane influx and efflux of mantle in Anodonta woodiano paciflca Heuda were studied with the method of 45Ca transmembranes determination. The results showed that high-concentration of KCl solution had no effect on the Ca2 + flux in mantle epithelium; CuSO4 was proved to inhib-ite Ca metabolism significantly

for it could decrease the Ca2 + influx of mantle in the concentration dependent manner

and Ca2+ influx decreased markedly even in 1μg/g CuSO4 compared with the control. The Ca2+ influx showed stable in the pH of 3-9

while pH increased to 11

the Ca2+ influx decreased to 1/6 of the others. We also examined the Ca2 + efflux of mantle in shell in calm condition

the results proved that the radioactivity in mantle was decreased gradually during 0-80 min.