Ion Channel Kinetics
An adherent CHO cell culture, expressing TRPV1, was used to demonstrate the application of the BioPen (formerly the Multifunctional pipette) for the delivery of ion channel agonist. More specifically, the effects of cholesterol depletion on the pore dilation of TRPV1 were investigated. The ion channels were activated with the agonists; capsaicin or protons (pH 5.5), and the ion-permeability properties of TRPV1 were assessed using whole-cell patch-clamp and YO-PRO uptake rate studies. While using the BioPen to locally perfuse agonists in tandem with YO-PRO, the uptake rate was monitored by measuring the intracellular fluorescence intensity using confocal microscopy. Cholesterol depletion was found to decrease TRPV1 mediated uptake rates of YO-PRO. Using localized perfusion enabled data libraries to be created from individual and small clusters of cells.