用激光共聚焦扫描技术研究昆虫触角叶的雌雄异构性

【目的】本研究探讨用激光共聚焦扫描显微镜对昆虫触角叶内结构的扫描技术。【方法】选取鳞翅目斜纹夜蛾Spodoptera litura, 蜚蠊目美洲大蠊Periplaneta americana和鞘翅目松墨天牛Monochamus alternatus, 仔细解剖得到昆虫完整脑组织, 经过Lucifer yellow染色、戊二醛固定、梯度酒精脱水和透明等一系列处理后, 用激光共聚焦扫描显微镜对昆虫触角叶结构进行分层扫描。【结果】结果显示: 经该方法处理后在激发光488 nm下能清晰扫描出昆虫触角内典型结构神经纤维球, 并且可清晰看到这3种昆虫雄性触角叶结构内的扩大型神经纤维球复合体(macroglomerular complex, MGC), 而在相应雌性昆虫体内都没有此复合体。另外通过5 μm分层扫描得到斜纹夜蛾、美洲大蠊和松墨天牛的触角叶平均厚度分别为130, 235和115 μm, 神经纤维球数量分别为35, 59和39个。【结论】激光共聚焦扫描技术是获得昆虫触角叶内部结构的一个可行方法。

Using confocal microscopy to study sexually dimorphic antennal lobes in insects

【Aim】 To study the sexually dimorphic antennal lobes (AL) of three insects from Lepidoptera, Blattaria, and Coleoptera. 【Methods】 The whole brains of female and male Spodoptera litura, Periplaneta americana, and Monochamus alternatus were dissected, stained with a fluorescent dye, fixed, and dehydrated, and then the structure of AL was scanned by using confocal microscopy. 【Results】 The results indicate that the macroglomerular complex (MGC), a specialized region in the AL for processing sex pheromones, is present in the males of all three species, but absent in the females. The size of the antennal lobe of these three insects varies considerably, with a measured depth of 130 μm, 235 μm and 115 μm, respectively. The number of glomeruli of these three species was 35, 59 and 39, respectively. 【Conclusion】 The technology of laser confocal scanning is an effective way to observe the structure of the antennal lobe of insects, and the results show a proof of concept for a larger investigation on the structure and function of antennal lobes across different orders.