首页 | 本学科首页   官方微博 | 高级检索  
     


Membrane conductance changes in single nodes of ranvier,measured by laser-induced temperature-jump experiments
Authors:L.E. Moore
Affiliation:Department of Physiology, School of Medicine, Case Western Reserve University, Cleveland, Ohio U.S.A.
Abstract:Temperature-jump experiments on isolated myelinated nerve fibers were done using a pulsed laser system in the Q switched mode. Voltage-clamp and temperature perturbations were used to measure the relaxing ionic conductances of both the Na+ and K+ systems. It is shown that the T jump can be used to probe the K+ and Na+ conductances during non-steady state conditions and thereby elicit relaxation times for a variety of initial states. Temperature-induced K+ conductance relaxation times were consistent with voltage-clamp measurements. The temperature-perturbation experiments were done as a combination of a temperature step and impulse change due to an adsorption of carbon black particles on the nerve. The experiments support the hypothesis that the relaxation times of the K+ system are independent of the previous history of the axon. It is concluded that the K+ conductance is at least a second-order system whose relaxation spectrum is composed of two exponential terms the magnitudes of which are markedly dependent on the initial conditions.
Keywords:
本文献已被 ScienceDirect 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号