镉短期经口暴露大鼠急性损伤效应研究

Study on Acute Injury Effects on Rats Caused by Short-term Oral Exposure to Cadmium

目的研究镉经口短期暴露(14和28 d)所引起的大鼠急性损伤效应。方法 SD雄性大鼠共72只,随机分为6组,包括阴性对照组和0. 4、0. 8、2. 0、5. 0和12. 5 mg/(kg·d)(以镉计)剂量组,每组12只。采用经口灌胃给予不同剂量的氯化镉,每日1次,连续染毒28 d。每周测定并记录体重、进行尿常规检测,于染毒后第14天和第28天分别处死每组6只大鼠。检测血清丙氨酸氨基转移酶(ALT)、天门冬氨酸氨基转移酶(AST)及血尿素氮(BUN)指标。取肝、肾、脾、脑和睾丸,分别称重计算脏器系数,并进行病理检测。结果与阴性对照组比较,5. 0和12. 5 mg/(kg·d)剂量组大鼠体重随灌胃剂量升高而降低(P<0. 01),染毒14 d 12. 5 mg/(kg·d)剂量组肾脏系数明显降低(P <0. 01),染毒28 d 5. 0和12. 5 mg/(kg·d)剂量组血清ALT升高有统计学意义(P<0. 05)。尿常规和组织病理学检查各实验组与阴性对照组相比均无统计学差异(P> 0. 05)。结论氯化镉短期暴露对大鼠有一定的急性损伤效应。

Objectives To study the acute injury effects of short-term oral exposure(14 or 28 days)to cadmium on rats.Methods A total of 72 male SD rats were randomly divided into 6 groups,including a negative control group as well as 0.4,0.8,2.0,5.0 and 12.5 mg/kg·d(cadmium)dose groups with 12 rats in each group.Rats were administered with different doses of cadmium chloride by gavage once a day for consecutive 28 days.Body weights were recorded and urine tests were carried out weekly.Six rats in each group were sacrificed in14 days and 28 days after exposure.Blood samples were obtained to detect alanine aminotransferase(ALT),aspartate aminotransferase(AST),and blood urea nitrogen(BUN).The liver,kidney,spleen,brain,and testis were collected and weighted respectively to calculate organ coefficients in addition to conducting pathological examination.Results Compared with the negative control group,the body weight in the 5.0 and 12.5 mg/(kg·d)dose groups decreased with the increase of dosage(P<0.01),the kidney coefficient of 12.5 mg/(kg·d)dose group was significantly decreased after 14 days(P<0.01).The increase of serum ALT in 5.0 and 12.5 mg/(kg·d)dose groups after 28 days had statistical significance(P<0.05).There was no significant difference in urine test or histopathology between the experimental group and the negative control group(P>0.05).Conclusions The result showed that the short term exposure to cadmium chloride had acute injury effects on rats to a certain degree.