Electrophysiological techniques in kidney micropuncture.

Electrophysiological techiniques lhave been wiclely uised for the investigation of membrane properties in excitable andl inexcitable tissues. The application of suclh metlho(ds to epitlhelia lhas been extensive, particuilarly for structures that can be mounte(d as an isolated tisstue slheet in special chambers designed to control the bathing soltutions. Witlh respect to the sttu(ly of the renal epithelium, electrical methods combine classical microptuncture approaclhes with intracelltular microelectrode techniquies. The anatomy of the tubular epithelium imposes a number of special problems. First, access to both boundaries of tlle tubular cell layer demands the tuse of special perfusion teclhniquies. Second, the maintenance of an optimal stability of the tubular wall is a matter of serious concern. Finally, the use of microelectrodes raises problems of exact localization of the electrode tip within the tubular epithelium.