The patch-clamp technique of Neher and Sakmann and their colleagues has been widely used over the last 5 years to investigate ion channels in excitable tissues. More recently, it has become useful as a tool to study channels involved in transepithelial ion transport. In this review, I briefly cover the basic concepts behind the patch-clamp technique and the kinds of information that can be obtained with it. I then summarize the applications of the technique to renal tissues and describe some of the channel types that have been observed to date in epithelia.
