Giant Patch and Macro Patch

The giant patch method was first developed in 1989. The major characteristic is the use of a pipette with a large tip diameter, which dramatically broadened the applications of the excised patch. The giant patch method enables (1) the current recording of transporters/channels with slow turnover rates and low expression levels, which had been impossible with the conventional method; (2) the rapid voltage-clamp; (3) rapid exchange of the bath and pipette solutions. We describe the devices and limitations for the application of the giant patch method to cardiomyocytes, Xenopus oocytes, and cultured cells. In addition, we describe another method, the macro patch, which we developed to overcome one of the limitations of the cardiac giant patch.