Analysis of the molecular mechanisms controlling synaptic transmission by patch-clamp recording in brainstem slices

The first article describing the patch-clamp recording from neurons in the mammalian brain slice appeared in 1989. Since that article, there have been substantial scientific successes in the neuropharmacological and neurophysiological fields using this promising technique, which itself advanced largely owing to the progress in microscopic techniques such as infrared differential interference contrast (IR-DIC) video-enhanced microscopy. This article describes recent advances in the methods for the patch-clamp recording in the brainstem slices, which is now more and more important due to the increased needs in this post-genomic era for identification of the mechanisms underlying cell-to-cell communication in the central nervous system. Here we introduce some of the technical tips developed and being used in our laboratory, which include methods for making the best brainstem slices, pre-recording identification of neuron types using fluorescent tracers, markers, and green fluorescent protein (GFP) signal in transgenic mice. We also describe a method for rapid and secure drug application onto the recorded cell using electromagnetic valves, which we term the "macro Y-tube" method. These techniques may help to accelerate the understanding of the molecular mechanisms underlying dynamic regulation of central nervous function.