本文主要研究了镉对小鼠肾脏的损伤程度及不同剂量条件下的四甲基尿酸对肾脏的保护作用效果。实验中采用对小鼠腹腔注射氯化镉建立氧化损伤肾脏组织模型。雄性昆明小鼠50只，随机分为空白组、损伤组、及低、中、高不同剂量保护组，共五组，每组十只。空白组和模型组灌胃等体积生理盐水，保护组依次用10 mg/kg、20 mg/kg、40 mg/kg的四甲基尿酸混悬液进行灌胃，连续处理14 d后，颈椎脱臼法处死，取出肾脏组织，检测肾脏内脂质过氧化(MDA)、蛋白羰基化(PCO)、一氧化氮(NO)、过氧化氢酶(CAT)、超氧化物歧化酶(SOD)、以及谷胱甘肽(GSH)的含量，观察肾病理变化。结果表明，与空白组相比，模型组肾脏组织中MDA、PCO、NO含量显著升高(p<0.01)，分别为空白组的1.89倍、3.32倍、1.64倍，而SOD、CAT、GSH活性显著降低(p<0.01)，分别为空白组的76.25%、77.12%、45.61%。与模型组相比，保护组均不同程度降低了肾脏组织中MDA、PCO、NO含量，提高了SOD、CAT、以及GSH活性，降低肾脏损伤的程度，病理切片显示，中剂量四甲基尿酸保护肾脏损伤效果最佳。由结果可知，四甲基尿酸对镉致小鼠肾脏损伤程度起到一定的保护作用，能有效降低肾脏氧化损伤程度并维持酶与抗氧化酶的平衡状态，其机制可能与抗氧化有关。

The degree of cadmium damage to kidney in mice and the protective effect of theacrine on kidney under different doses were studied. In the research, the model of oxidative damage of kidney tissue in mice was established by intraperitoneal injection of cadmium chloride. Fifty male Kunming mice were randomly divided into blank group, injury group and low, medium and high dose protection group, with 10 mice in each group. The blank group and model group were given normal saline of equal volume by gastric perfusion, in the protective group were given theacrine suspension of 10 mg/kg, 20 mg/kg, 40 mg/kg by gastric perfusion. After 14 days of treatment, cervical dislocation was performed and kidney tissues were taken out. The contents of lipid peroxidation (MDA), protein carbonylation (PCO), nitric oxide (NO), catalase (CAT), superoxide dismutase (SOD), and glutathione (GSH) in the kidney were detected. The pathological changes of nephropathy were observed. The results showed that compared with the blank group, the contents of MDA, PCO and NO in the kidney tissue of the model group increased significantly (p<0.01), which were 1.89, 3.32 and 1.64 times content of the blank group respectively, while the activities of SOD, CAT and GSH decreased significantly (p<0.01), only 76.25%, 77.12% and 45.61% of the blank group respectively. Compared with the model group, the protective group reduced the contents of MDA, PCO and NO, increased SOD, CAT and GSH activities, and reduced the degree of kidney injury. Pathological sections showed that middle dose of theacrine had the best protective effect on kidney injury. The results showed that theacrine had protective effect on cadmium-induced renal injury in mice. It can effectively reduce the degree of oxidative damage and maintain the balance between enzymes and antioxidant enzymes. The mechanism may be related to antioxidant activity.

陕西省科技厅一般项目-农业领域（2017NY-1030）；陕西省科技厅一般项目-农业领域，农业部农产品加工重点实验室开放基金（2017KF-07）；陕西省缺血性心血管疾病重点实验室开放基金（2016ZDKF-05）