利用单感器记录与神经元示踪结合对棉铃虫主要性信息素感器内神经元投射的鉴定

【目的】鉴定雄性棉铃虫Helicoverpa armigera成虫触角性信息素感器嗅觉受体神经元的功能、形态及中枢投射路径。【方法】利用单感器记录技术记录棉铃虫嗅觉受体神经元对性信息素的反应,同时采用荧光染料作为示踪剂染色标记嗅觉受体神经元;使用免疫组织化学方法处理相应的脑组织,标记脑内触角叶的神经纤维球结构;用激光扫描共聚焦显微镜获取图像数据,使用图形软件ZEN和Amira 4.1.1进行三维结构重建。【结果】记录到雄性棉铃虫成虫触角上长毛形感器对主要性信息素成分Z11-16∶Ald产生明显的电生理反应,并成功染色标记了该感器内的嗅觉受体神经元。染色标记显示该感器内具有两个嗅觉受体神经元,其轴突通过触角神经分别投射触角叶内的云状体神经纤维球和普通神经纤维球。【结论】单感器记录与神经元示踪两技术结合能够用于鉴定昆虫触角嗅觉受体神经元的功能、形态和投射至神经纤维球的路径。与赖氨酸钴方法比较,使用荧光染料法进行神经元示踪,操作更简便,且易于进行三维空间分析,为调查棉铃虫其他嗅觉神经元的投射路径以明确外周气味受体感受与中枢系统的联系提供了有力技术支持。

Projection of major pheromone tuned olfactory receptor neurons ofHelicoverpa armigera(Lepidoptera: Noctuidae) revealed by using single sensillum recording and staining

【Aim】 To characterize the function and morphology of major pheromone tunedolfactory receptor neurons and their central projection to the brain in the cottonbollworm, Helicoverpa armigera. 【Methods】 Single sensillum recording was used to recordthe response of major pheromone tuned olfactory receptor neurons to sex pheromones, andstaining with a fluorescent dye used to label the neurons. Immunohistochemistry was used tolabel the antennal lobe glomeruli. Laser scanning confocal microscope was used to acquirethe images of antennal lobes with stained neurons, and the image software ZEN and Amira4.1.1 was used to analyze the data. 【Results】 Obvious electrophysiological responses oftrichoidea sensilla on the antennae of male adults of H. armigera to the major pheromonecomponent Z11-16∶Ald were recorded, and the olfactory receptor neurons housed in thesensilla were successfully labeled by staining. Two olfactory receptor neurons wereobserved in Z11-16∶Ald-responsive sensllium. The axons of these two olfactory receptorneurons project via the antennal nerve to the cumulus and an ordinary glomerulus in theantennal lobe, respectively. 【Conclusion】 The combination of single sensillum recordingand staining with the fluorescent dye can be applied in the identification of the functionand morphology of olfactory receptor neurons housed in the antennal sensilla of insects andtheir central projection pathway to the antennal lobe glomeruli. Compared with the cobalt-lysine, the staining with fluorescent dye is more practical and facilitates the imageacquisition and three-dimensional reconstruction. Such method provides technical supportfor the investigation on the projection pathway of other olfactory receptor neurons of H.armigera to determine the relationship between the peripheral odor receptor perception andthe central nervous system.