慢性氟中毒大鼠睾丸组织总抗氧化能力与一氧化氮合酶和一氧化氮水平的变化

The Level of Total Anti-oxidation Capacity, Nitric Oxide Synthase and Nitric Oxide in Testis of Chronic Fluorosis Rats

目的通过给实验大鼠饮用不同浓度的氟化钠溶液,造成慢性氟中毒,测定实验大鼠睾丸组织匀浆中总抗氧化能力(T-AOC)、超氧化物歧化酶(SOD)与一氧化氮合酶(NOS)活力和一氧化氮(NO)的含量。方法选用Wistar雄性大鼠24只,分为对照组、低氟组、高氟组,每组8只,染氟组分别自由饮用含氟化钠(NaF)100mg/L、200mg/L的自来水,对照组自由饮用自来水。20周后处死动物,留取睾丸,制备匀浆。采用比色法检测T-AOC及NOS活力;采用黄嘌呤氧化酶法检测SOD活力;采用硝酸还原酶法检测NO含量。结果低氟组与对照组比较,T-AOC明显增加(P<0.01);而高氟组与对照组比较,则明显降低(P<0.01)。SOD活力在各组间比较,差异无统计学意义。与对照组比较,低氟组NOS活力、NO含量均明显减少(P<0.01);而高氟组NOS活力、NO含量均明显升高(P<0.01)。结论低剂量氟可能通过抑制NOS活力和NO的合成而使T-AOC代偿性增加;高剂量氟可能使活性氧增加,诱导型一氧化氮合酶(iNOS)开始异常表达而使NO合成增加。

Objective To explore the total anti-oxidation capacity(T-AOC), superoxide dismutase(SOD), nitric oxide synthase(NOS) and nitric oxide(NO) in testis homogenate of the rats’ with chronic fluorosis induced by drinking NaF solutions with different concentration. Methods 24 male Wistar rats were divided into 3 groups (8 rats per group) including control group, low-fluoride(LF) group, high-fluoride(HF) group, which were exposed to fluoride by means of freely drinking tap water containing NaF with 0, 100 and 200 mg/L respectively for 20 weeks. T-AOC, NOS activities and SOD activity of the testis tissue were determined by colorimetry , xanthine oxidase method and nitrate reductase method respectively. Results Compared with the control group, the T-AOC of the testis tissue increased significantly in LF group and decreased significantly in HF group. SOD activity of the testis tissue showed on significant difference among the control group, LF group and HF group . Compared with the control group, the levels of NOS and NO decreased significantly in LF group and increased significantly in HF group. Conclusion The T-AOC of the testis tissue exposed to low level of fluoride presents a compensatory increase induced by the inhibited activity of NOS and synthesis of NO. Higher level of fluoride may increase reactive oxygen species(ROS), and cause abnormal expression of induce nitric oxide synthase(iNOS) and increased synthesis of NO in the testis tissue.