氯硝柳胺悬浮剂对日本血吸虫尾蚴影响的酶组织化学观察

Enzyme-histochemical observation on influence of suspension concentrate of niclosamide in cercariae of Schistosoma japon-icum

目的采用酶组织化学技术,观察经氯硝柳胺悬浮剂处理后的日本血吸虫尾蚴体内酶活性变化,以研究其杀蚴机制。方法将正常尾蚴和经氯硝柳胺悬浮剂浸泡后的尾蚴粘附于盖玻片上,室温晾干;分别对2组尾蚴进行细胞色素C氧化酶(CCO)、乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)、乙酰胆碱酯酶(AChE)和一氧化氮合酶(NOS)的酶组织化学染色;常规法制片,显微镜观察着色反应;采用显微图像分析系统定量测定其平均灰度值。结果CCO、LDH、SDH、AChE和NOS在尾蚴的头器、腹吸盘和尾干部位的酶活性较高。其中用药组CCO、LDH和NOS的活性明显高于对照组,SDH用药组和对照组的活性变化差异无显著性,而AchE用药组的活性明显低于对照组。结论氯硝柳胺引起尾蚴耗能加剧导致机体的能量供应障碍,能量的短时间耗竭是引起尾蚴死亡的主要原因之一。

Objective To observe the changes of enzyme activity in cercariae of Schistosoma japonicum treated with suspension concentrate of niclosamide by the enzyme-histochemical technique and to explore the killing mechanism of the suspension concentrate of niclosamide against cercariae. Methods The normal cercariae and the cercariae treated with suspension concentrate of niclosamide were attached on the cover glasses and dried in room temperature. The stain of enzyme-histochemistry for CCO, LDH, SDH,AChE and NOS was done, and then the staining block was made by the routine method. The staining reaction in the tissues of cercariae was observed with microscopy and the average gray density was also observed with the image analysis system of biomicro-scope. Results CCO, LDH, SDH, AChE and NOS had the extensive distribution in cercariae. The enzyme activity was high in the head organ, ventral sucker and tail stem of cercariae. The enzyme activity of CCO, LDH and NOS in the treated group was significantly higher than that in the control group. The enzyme activity of SDH was not significantly different between the two groups. The enzyme activity of AChE in the treated group was significantly lower than that in the control group. Conclusion Niclosamide could cause the rapid consuming of energy during short time and result in disturbance of energy in cercariae, which is one of the main reasons causing death of cercariae.