The Giant Membrane Patch

Abstract

This chapter describes methods to form and excise membrane patches with diameters of 12 to 40 µm, capacitances of 2 to 15 pF, and seal resistances of 1 to 10 GΩ. The formation of such “giant” membrane patches (Hilgemann, 1989) has been successful with most cells that allow gigohm seals to be formed with conventional patch-clamp techniques. Cell types employed to date for inside-out patches include Xenopus oocytes, cardiac myocytes, skeletal myocytes, tracheal myoctes, Lymnaea snail neurons, SF9 cells, chromaffin cells, pancreatic acinar cells, and some blood cells. Up to now, a successful procedure to form giant outside-out patches routinely has been developed only for Xenopus oocytes (Rettinger et al., 1994).