Single Channel Measurements

Smith, J.S., Coronado, R., Meissner, G. (1986). Single channel measurements of the calcium release charmel from skeletal muscle sarcoplasmic reticulum. J. Gen. Physiol. 88, 573-588. 

Single-channel measurements of 39 in planar bilayers revealed three types of independent but constant conductance levels. These comprised (i) high conductance levels (700-1400 pS) which stayed open almost indefinitely (ii) an intermediate level (70-100 pS) with millisecond opening and closing kinetics, and (iii) a low conductance level (10.85 1.58 pS) which showed relatively slow gating. The... 

The Xenopus oocyte expression system can be used to study macroscopic junctional conductances, but not to make single-channel measurements. Dual voltage clamp of coupled cells under conditions of reduced junctional conductance can reveal single-channel transitions (41, 46), but the problems of accessibility and series hemichannels remain. 

Single channel measurements show that BIDN and fipronil reduce mean open time and increase the mean closed time, which is consistent with an open-channel blocking mechanism [27, 62). 

This section considers the response measurement of a single-degree-of-freedom system or a single-channel measurement of a multi-degree-of-freedom system. Discrete data is sampled with a time step Ar and y denotes the measured response at time t = nAt. The measurement is different from the model response ... 

In the following, I will outline some of the basic considerations that are required for single channel resolution. Based on that I will describe the principles of the patch clamp method and then illustrate some of the properties of Acetylcholine receptor channels by means of single channel measurements. 

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