Sugino K, Machemer H
Arbeitsgruppe Zelluläre Erregungsphysiologie, Fakultät für Biologie, Ruhr-Universität, Bochum, Federal Republic of Germany.
Cell Motil Cytoskeleton. 1988;11(4):275-90. doi: 10.1002/cm.970110406.
Motor responses of the frontal cirri of the ciliate Stylonychia were recorded at the axial view of the ciliary base with high-speed cinematography. Voltage-clamp applying sustained hyperpolarizing voltage steps was used to explore the properties of the ciliary cycle modulated by the membrane potential. Upon hyperpolarization between -1 and -13 mV, a previously inactive frontal cirrus reoriented from a neutral posture and started beating so that the axis of the beating cone of a proximal cirral segment assumed an orientation near 100 degrees (proceeding counterclockwise from posterior = 0 degrees) and inclination near 60 degrees (0 degrees = perpendicular to the cell surface). The major beating amplitude was limited to about 150 degrees. Increasing hyperpolarization increased the spatial polarity of the cycle (ratio of major over minor amplitude, from 2 to 2.4). Rates of the power stroke increased with hyperpolarizations up to -4 mV but were consistently smaller than those of the return stroke during the ciliary cycle (ratio: 0.4 to 0.6; = temporal polarity). Comparison of different hypothetical beat forms (0-shape, D-shape, and egg-shape) showed that the orientation-time data are the major determinants of the angular velocity and rate of reorientation of the cilium during the cycle. Geometric transformation of these data led to descriptions of the cycle of a proximal ciliary segment in terms of active sliding velocities and rates of unidirectional sliding translocation between identified doublets. Three voltage-sensitive functional parameters of the cilium--the inclination (which is noncyclic) and the rates of active sliding and sliding translocation (both of which are cyclic in nature)--are discussed as generating the spatial and temporal properties of the ciliary beat.
利用高速摄影技术，在纤毛基部的轴向视图下记录了纤毛虫Stylonychia额部纤毛的运动反应。采用施加持续超极化电压阶跃的电压钳技术，来探究由膜电位调制的纤毛周期特性。在 -1 至 -13 mV 的超极化状态下，先前静止的额部纤毛从自然姿势重新定向并开始摆动，使得近端纤毛段的摆动锥轴的方向接近 100 度（从后 = 0 度逆时针方向），倾斜度接近 60 度（0 度 = 垂直于细胞表面）。主要的摆动幅度限制在约 150 度。超极化程度增加会使周期的空间极性增加（主振幅与次振幅之比，从 2 增加到 2.4）。在纤毛周期中，动力冲程的速率随着超极化增加到 -4 mV 而增加，但始终小于返回冲程的速率（比率：0.4 至 0.6； = 时间极性）。对不同假设的摆动形式（0 形、D 形和卵形）的比较表明，方向 - 时间数据是纤毛在周期中角速度和重新定向速率的主要决定因素。这些数据的几何变换导致了根据活性滑动速度以及确定的双联体之间单向滑动易位的速率，来描述近端纤毛段的周期。讨论了纤毛的三个电压敏感功能参数——倾斜度（非周期性）以及活性滑动和滑动易位的速率（两者本质上都是周期性的）——作为产生纤毛摆动的空间和时间特性的因素。
