MECHANICAL AND ELECTRIC CORRELATES OF MECHANORECEPTOR ACTIVATION OF THE CILIATED TAIL IN PARAMECIUM
MECHANICAL AND ELECTRIC CORRELATES OF MECHANORECEPTOR ACTIVATION OF THE CILIATED TAIL IN PARAMECIUM
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DOI：
10.1007/bf00604993
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发表时间：
1984-01-01
期刊：
影响因子：
--
通讯作者：
MACHEMERROHNISCH, S
中科院分区：
文献类型：
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作者：
MACHEMER, H;MACHEMERROHNISCH, S
通过微针将单个机械脉冲施加到草履虫敏感的后体膜上，该膜具有一束不动且细长的尾部纤毛。使用膜电压钳和显微照相术记录刺激和反应事件的时间顺序。使用去纤毛技术来确定纤毛在受体电流产生中的作用。受体电流的最小潜伏期在 2-2.5 ms 之间。在电流上升之前，体膜以W形方式变形，细胞末端变宽并向前移动。当刺激幅度较小时，受体电流的第一个迹象包括大约 .apprx 的额外延迟。 5 毫秒。当刺激幅度提高时，会突然过渡到正常反应潜伏期。刺激幅度决定了受体电流的速率和幅度。刺激速率的降低会增加反应潜伏期。在体膜从压痕反弹期间，受体电流继续流动。此时尾部纤毛被动偏转。使用 5% 乙醇和机械搅拌进行细胞去纤化不会影响最小反应潜伏期，但会降低尾部区域的敏感性。乙醇处理的纤毛细胞比正常细胞更敏感。通过纤毛的刺激传导可以增强受体反应。受体电流的潜伏期似乎受到位于体细胞中的转导机制的限制。尾部纤毛用于传递刺激，可能包括非局部机械输入的空间和时间总和。
Single mechanical pulses were applied by microneedle to the sensitive posterior soma membrane of Paramecium which bears a bundle of immobile and elongated tail cilia. The time sequence of events of stimulation and response was recorded using membrane voltage clamp and microphotography. Deciliation techniques were used to determine the role of cilia in receptor current generation. The minimal latency of the receptor current was between 2-2.5 ms. Prior to the rise of the current the soma membrane was deformed in a W-shaped manner, the cell end had widened and shifted anteriorly. With small stimulus amplitudes 1st signs of the receptor current included an additional delay of .apprx. 5 ms. Abrupt transition to the normal response latency occurred upon raising the amplitude of the stimulus. The stimulus amplitdue determined the rate and amplitude of the receptor current. Decreasing rates of the stimulius increased the response latency. The receptor current continued to flow during somatic membrane rebound from indentation. At this time tht tail cilia were passively deflected. Cell deciliation using 5% ethanol and mechanical agitation did not affect the minimal response latency, but decreased the sensitivity of the tail area. Ethanol-treated ciliated cells were more sensitive than normal cells. Stimulus conduction via the cilia can enhance the receptor response. The latency of the receptor current appears to be limited by a transduction mechanism located in the soma. The tail cilia serve to transmit the stimulus including, presumably, spatial and temporal summing of non-local mechanical input.