カエル単一筋線維における局所収縮の伝播について

概要

論文の詳細を見る
A small area of the surface membrane of a muscle fibre isolated from the semitendinosus of the frog (Rana japonica) was depolarized by applying current pulses to a pipette whose tip (diameter 3-20μ) was made in contact with the fibre surface. The magnitude of depolarization was roughly determined by measuring the contact resistance of the pipette and multiplying the applied current. Besides the graded inward spread of contraction described by Huxley and Taylor (1958), the fibres showed another type of local contraction in response to depolarization of more than 100-300mV and of 100-300 msec duration. It will be seen that, in comparison with the resting fibre, the shortening of sarcomere length is observable not only under the pipette but also at the other side of the fibre surface. Such an appearance results from that the contraction spreads transversely around the whole fibre perimeter and not through the center of the fibre. The average velocity of the spreading is of the order of 1cm/sec. This response can also be elicited in choline-Ringer's solution. The transverse compornent(s) of sarcoplasmic reticulum may be involved in this response.
社団法人日本動物学会の論文
1965-06-15