氯硝柳胺悬浮剂对钉螺影响的酶组织化学观察

目的观察氯硝柳胺悬浮剂对钉螺体内酶活性的影响,以研究其杀螺机制。方法实验钉螺采集于江苏省镇江市丹徒区有螺江滩,分为2组:用药组钉螺采用25%氯硝柳胺悬浮剂,按2.0g/(L·m2)进行喷洒,对照组钉螺采用蒸馏水喷洒。钉螺去壳后分离出软体,置冰冻切片机切片,按常规进行细胞色素C氧化酶(CCO)、乳酸脱氢酶(LDH)、琥珀酸脱氢酶(SDH)、胆碱酯酶(CHE)和一氧化氮合酶(NOS)的酶组织化学染色、制片,显微镜下观察着色反应结果,采用显微图像分析系统定量测定并比较灰度值。结果用药组钉螺CCO、LDH、SDH、CHE和NOS定位口囊、肌纤、表膜、神经节、肝脏、咽管等部位的酶活性明显低于对照组。结论氯硝柳胺影响钉螺体内神经介质传递和能量供应障碍,导致钉螺的各项生理功能紊乱和丧失,是引起钉螺死亡的原因之一。

Enzyme-histochemical observation on influence of suspension concentrate of niclosamide in Oncomelania hupensis snails

Objective To observe the influence of suspension concentrate of niclosamide on the enzyme activity of Oncomelania hupensis in order to explore its molluscicidal mechanism. Methods Oncomelania hupensis snails were collected in the habitates of river marshland in Dantu District, Zhenjiang City, Jiangsu Provence and were divided into 2 groups. The snails of the treated group were sprinkled with 25% suspension concentrate of niclosamide. The snails of the control group were sprinkled with distilled water. The soft body tissue of the snail was separated and the sections of snail tissue were made in the Cryostat Microtome. The stain of enzyme-histochemistry showed CCO, LDH, SDH, CHE and NOS had been done, and then the staining block was made by routine method. The staining reaction in the snail tissue and the average gray density were observed with the image analysis system of biomicroscope. Results The enzyme activity of CCO, LDH, SDH, CHE and NOS located in the mouth, muscle fiber, tegumentary membrane, ganglia, liver and pharyngeal cavity of Oncomelania hupensis snails. The enzyme activities of CCO, LDH, SDH, CHE and NOS in the treated group were significantly lower than that in the control group. Conclusions Niclosamide can affect the transmitting of neurohypophysis and obstruct the energy and result in the disorder of the physiological functions in Oncomelania hupensis. It is one of the reasons of Oncomelania hupensis death.