亚硒酸钠对急性和亚慢性镉毒性的拮抗作用

Antagonistic Effects of Sodium Selenite Against Acute and Subchronic Toxicity of Cadmium

目的探讨急性、亚慢性镉染毒对大鼠的肝、肾毒性以及亚硒酸钠(Na2SeO3)对镉染毒大鼠肝、肾毒性的拮抗作用。方法急性实验时,Na2SeO3干预组大鼠以10μmol/kg腹腔注射Na2SeO3溶液,对照组和镉染毒组腹腔注射0.9%氯化钠。2 h后,干预组和镉染毒组大鼠皮下注射氯化镉(CdCl2)溶液35μmol/kg,对照组皮下注射0.9%氯化钠。亚慢性实验时,大鼠皮下注射CdCl2溶液7μmol/kg,每周5 d,1次/d,连续6周。然后Na2SeO3干预组大鼠腹腔注射Na2SeO3溶液10μmol/kg,共2周,对照组在相同时间注射0.9%氯化钠。测定大鼠血清、尿液和肝、肾组织中各酶的活力。结果急性镉染毒使大鼠血清乳酸脱氢酶(LDH)、丙氨酸转氨酶(ALT)活力明显升高,肝谷胱甘肽(GSH)、丙二醛(MDA)含量明显升高,谷胱甘肽过氧化物酶(GSH-Px)、超氧化物歧化酶(SOD)活力明显下降。Na2SeO3预处理可使急性镉染毒大鼠血清ALT、LDH活力分别降低至单纯镉染毒组的63.8%(166.61,261.11)和30.1%(40.85,135.52),差异有统计学意义(P<0.01),肝GSH、MDA含量明显降低,而GSH-Px、SOD活力明显升高。亚慢性镉染毒使大鼠尿碱性磷酸酶(ALP)、N-乙酰-β-苷酶(NAG)活力和尿蛋白含量明显升高,肾皮质GSH、MDA含量明显升高,GSH-Px活力明显降低。Na2SeO3处理使亚慢性镉染毒大鼠尿ALP酶活力明显下降,肾皮质GSH、MDA含量明显降低,GSH-Px活力明显升高。结论Na2SeO3对急性镉染毒所致肝损伤具有明显的保护作用,对亚慢性镉染毒致肾损伤的恢复具有一定的促进作用。

Objective To study antagonistic effects of sodium selenite （Na2 SeO3 ） on hepatotoxicity and nephrotoxicity of rats with acute and subchronic exposure to cadmium. Methods In acute experimentation, Wistar rats were injected ip with 10 gmol/kg Na2SeO3 in Na2SeO3 intervening groups and 0.9% NaCI in control and cadmium exposed groups. After 2 h the rats were injected subcutaneously with 35 μmol/kg CdCl2 solution in Na2SeO3 intervening and cadmium exposed groups and 0. 9% NaCI in control groups, In subchronic experimentation, rats were injected subcutaneously with 7 μmol/kg CdCl2 solution, 5 times a week, continuously for 6 weeks. The Na2SeO3 intervening group was injected ip with 10 gmol/kg Na2SeO3 for 2 weeks while the control group were injected ip with 0.9% NaCI, The activities and contents of some enzymes were determined in serum, urine, liver and kidney cortex. Results For the rats in acute exposure to cadmium, LDH （lactic dehydrogenase） and ALT （alanine transferase） activities in serum obviously increased. GSH （glutathion） and MDA （malondialdehyde） contents in liver increased significantly and GSH-Px （glutathion peroxidase） and SOD activities lowered obviously. The pretreatment of Na2SeO3 may significantly reduce the activities of LDH and ALT to 63.8% （166.61, 261.11） and 30.1% （40.85, 135.52） respectively in serum comparing with cadmium exposed group （ P 〈 0. 01）. The pretreatment of Na2SeO3 may significantly lower GSH and MDA contents in liver, while the activities of GSH-Px and SOD significantly increased. For rats in subchronic cadmium exposed group, activities of ALP and NAG and protein contents in urine increased obviously, and contents of GSH and MDA increased obviously while GSH- Px activity obviously decreased in renal cortex. The injection of Na2 SeO3 may significantly reduce ALP activity in urine, and may also significantly reduce GSH and MDA contents while GSH Px activity increased in renal cortex. Conclusions Na2SeO3 might have protective effects on acute hepatotoxicity and promotive effects on recovery of subchronic nephrotoxicity induced by Cd.