Recording from Macropatches

The purpose of this chapter is to describe the procedures used to record macroscopic currents from patches of biological membranes. Several variations of the classic patch-clamp recording procedure are available and described in other chapters of this book, however the procedure reported here is unique from single-channel recording, loose patch-clamp recording, and giant-patch recording. Like single-channel recording and giant-patch recording, macropatch recording requires the formation of a tight seal between the recording pipet and the membrane. However, the size of the pipet tip used for macropatch recording is typically larger than that used in single-channel recording and considerably smaller than the pipets used for giant-patch recording (see Subheading 3.2.3. ). It is possible using macropatch recording to determine both the identity of currents as well as their spatial distribution in biological membranes.