A Microfluidic Assay for Measuring Electrical Conductivity of Gap Junction Channels

Abstract

ABSTRACTWe have developed a microfluidic sensor to measure the electrical coupling through gap junctions across a 2D sheet of cultured Normal Rat Kidney cells. The chip is based on a tri-stream laminar flow with conductive solutions on either end and a nonconductive solution in the middle stream. When an electrical voltage is applied, the current can only pass through the cell sheet, thereby enabling us to measure the electrical coupling of gap junctions between cells. Using this sensor we have measured the effect of 2-aminoethoxydiphenyl borate (2-APB) on Cx43 channels. We show that 2-APB reversibly inhibits electrical coupling of Cx43 in NRK cells. Moreover, we screened other potential candidates to block Cx43, 1-Heptanol and GsMTx-4, and examined their effects on Cx43 gap junctions.