镉对大鼠肾皮质钙泵和钠泵活性的影响

The Effect of Cadmium on Ca Pump and Na Pump of Kidney Cortex in Rats

给大鼠皮下注射不同剂量的镉金属硫蛋白（ＣｄＭＴ）后１２ｈ，染镉组大鼠尿镉、尿钙和尿蛋白含量高于对照组，且与给予的镉剂量间呈正相关；肾皮质钙泵和钠泵的活性随染镉剂量增大则逐渐降低，两者呈负相关。体外试验中，镉能抑制钙泵活性，这种抑制作用能被谷胱甘肽（ＧＳＨ）和Ｌ半胱氨酸所消除。结果表明，镉对钙泵和钠泵的抑制作用是其引起钙尿症的机理之一。

Rats were injected subcutaneousily with cadmium metallothionein(CdMT) in different dose.The dose dependent increasing of urinary Cd,Ca and protein,and dose dependent decreasing of Na + K +-ATPase (Na pump)and Ca 2+ ATPase(Ca pump)activities of kidney cortex were observed 12 hours after CdMT injetion.The Ca pump activity of kidney cortex was inhibited by Cd in vitro study,but it could be protected in the presence of glutathione(GSH) or L systeine.The result showed that the inhibition of Ca pump and Na pump of kidney cortex is one of mechanisms that Cd resulted in calciuria,and GSH and L systeine played a protective role in the inhibition of Ca pump of kidney cortex induced by Cd.