家蝇对病原入侵黑化反应的研究

Study on melanization response of Musca domestica while confronting with the invading of different pathogens

目的探讨不同病原入侵对家蝇黑化反应的影响。方法以空的注射器针头刺激和生理盐水刺激为对照,对大肠杆菌、金黄色葡萄球菌单独刺激和两菌混合后一起刺激的家蝇成蝇、幼虫和蛹的黑化变化做形态解剖观察,并用分光光度计检测刺激样品的酚氧化酶活性变化。结果细菌刺激使幼虫的黑化时间明显缩短,3种菌刺的效果是混和菌﹥大肠杆菌﹥金黄色葡萄球菌,这与3种菌刺引起的家蝇样品中酚氧化酶活性增强的趋势一致。结论大肠杆菌和金黄色葡萄球菌混合菌刺激能够使家蝇出现强的黑化反应。

Objective To investigate the melanization responses to the invasions of different pathogenes in Musca domestica. Methods The empty syringe needle, physiological saline, Escherichia coli, Staphylococcus aureus and the mixture of E. coli and S. aureus were respectively used to stimulate the adult, 3-instar larvae and pupas of Musca domestica. Their melanization reactions were observed by the morphological and anatomical methods. Meanwhile, the phenoloxidases activity in samples-stimulated were determined with spectrophotometer. Results The times of mela- nization-detected in samples of bacteria-challenged got obvious shorter than that in samples-challenged by saline or empty syringe needle. The stimulation effects were different according to the different bacteria, the strongest was from the mixture of E. coli and S. aureus, the next was from E. coli, and the weakest was from S. aureus. The increasing tend- ency of phenoloxidases enzyme activity was consistent to the melanization changes in samples-challenged by bacteria of E. coli and S. aureus. Conclusion The stimulation from the mixture of E. coli and S. aureus can make housefly to appear strong melanization.