General Anesthetics and Single-Channel Recording

Kim, Kyoung Hun; Shin, Woo Jong

Abstract

Introduction of patch-clamp techniques allowed an increase in resolution of membrane current recordings. However, the technique was limited by apparent need for direct contact of pipette with cell membrane. Thus, this technique was restricted to isolated or cultured cell preparation. Although much has been achieved with such preparations, the studies of synapsis between cultured cells are undefined. Many of these problems were overcome by application of patch-clamp techniques to brain-slices. The use of high-resolution optics allowed visualization of cells to be recorded. It was possible to remove tissue covering cells and record currents in synaptically connected neurons. The brain-slice technique has greatly facilitated the investigation of electrical properties of neurons and the analysis of synaptic transmission between neurons. "Blow and seal"technique, when combined with infrared differential interference contrast video microscopy, permits recording of membrane potential and currents, not only from large cell body of neurons, but also from small processes. The technique offers many advantages, such as the case with which patch-pipette recordings can be made, the possibility of identifying cell type prior to recording and finally, the ability to visualize and record electrical activity from different compartments or from more than one site in the same neuron.