THE FINE STRUCTURE OF COCKROACH CAMPANIFORM SENSILLA
THE FINE STRUCTURE OF COCKROACH CAMPANIFORM SENSILLA
复制标题
蟑螂钟形感器的精细结构
作者：
D. Moran;K. M. Chapman;R. Ellis
蟑螂腿上的钟状感器为研究机械感受性感觉传递提供了一个良好的模型系统。本文描述了蟑螂胫骨钟状感器的光镜和电镜结构。钟状感受器是与外骨骼相关的本体感受机械感受器。每个感器的功能集中在单个初级感觉细胞周围，这是一个大型双极神经元，其40 µ宽的细胞体可用于细胞内微电极的电生理研究。它的轴突到达中枢神经系统;它的树突产生与角质层相关的修饰的纤毛。20 µ长的树突顶端含有一个基体，从基体上产生一个9 + 0连接纤毛。这种纤毛穿过角质层中的管道，直径扩大成为感觉过程，一个由350-1000个平行微管组成的膜限制束。感觉过程的尖端牢固地附着在一个薄的外表皮帽上;这个帽的机械凹陷，可能发生在行走运动中，有效地刺激了感觉器。提出了蟑螂钟状感受器感觉过程中微管在机械电传递中起重要作用的假说。
Campaniform sensilla on cockroach legs provide a good model system for the study of mechanoreceptive sensory transduction. This paper describes the structure of campaniform sensilla on the cockroach tibia as revealed by light- and electron-microscopy. Campaniform sensilla are proprioceptive mechanoreceptors associated with the exoskeleton. The function of each sensillum centers around a single primary sense cell, a large bipolar neuron whose 40 µ-wide cell body is available for electrophysiological investigation with intracellular microelectrodes. Its axon travels to the central nervous system; its dendrite gives rise to a modified cilium which is associated with the cuticle. The tip of the 20 µ-long dendrite contains a basal body, from which arises a 9 + 0 connecting cilium. This cilium passes through a canal in the cuticle, and expands in diameter to become the sensory process, a membrane-limited bundle of 350–1000 parallel microtubules. The tip of the sensory process is firmly attached to a thin cap of exocuticle; mechanical depression of this cap, which probably occurs during walking movements, effectively stimulates the sensillum. The hypothesis is presented that the microtubules of the sensory process play an important role in mechanoelectric transduction in cockroach campaniform sensilla.