镉对肾脏的毒作用

STUDY ON THE MECHANISM OF RENAL DAMAGE INDUCED BY CADMIUM IN RATs

雄性Ｗｉｓｔａｒ大鼠２４只，随机等分为４组，皮下注射不同剂量的ＣｄＭＴ。结果显示镉接触组尿钙和尿蛋白都高于对照组；肾皮质钠泵和钙泵活性低于对照组，体外试验也显示镉能抑制钙泵活性，ＧＳＨ和半胱氨酸对这种抑制有保护作用；肾皮质ＧＳＨ含量低于对照组，ＭＤＡ含量则高于对照组，但肝脏的这两个指标无变化；高剂量组ｃＡＭＰ／ｃＧＭＰ的比值低于对照组。提示脂质过氧化和钙代谢障碍是镉引起肾损害的机理之一。

Twenty-four male Wistar rats were divided Into 4 groups and injected subcutaneously with CdMT in the doses of 0,0.3,0.6 and 0.9 mg Cd/kg respcctively。 The results showed that the contents of urinary Cd,Ca and protein in the rats treated with Cd were higher and the activities of Na pump and Ca pump in renai cortex were Iower than those of control.A lower content of GSH and a higher content of MDA in renal cortex were also observed in the groups treated with Cd.In the highest dose of Cd group,cAMP/cGMP ratio was lower than that In control. A concentration depen-dent inhibition of Ca pump activity induced by CdCl2 in vitro study was also shown,but it could be protected in the presence of GSH or L-cysteine,It is suggested that lipid peroxidation and disturbance of Ca metabolism may be one of the mechanism in renal damage induced by Cd。