Stretch-activated ion channels in cultured mesangial cells

Membrane stretch, delivered by negative pressures in cell-attached patch pipettes, activated single-channel ionic currents in cultured mesangial cells. Channel opening probabilities were directly related to degree of suction, with threshold for activation being 5-10 mm Hg. The stretch-activated channels were permeable to Na+, K+, as well as Cl-, having conductances averaging 62 +/- 17 pS. These channels may represent a cellular mechano-reflex in mesangial cells.