Ethanol increases K+ conductance in human T-cells.
Ethanol increased the open probability of a K channel in cultured human T-cells. Single-channel currents were studied using the patch-clamp technique in cell-attached configuration. Ethanol increased the number of simultaneously active channels and subsequent current maxima at concentrations of 35 and 50 mM from control levels of 3.2 to 4.6 pA and 8.4 pA, respectively. Current responses were elicited by a 80 mV hyperpolarizing pulse following adjustment to the same resting potential. The channel was K-selective as determined by the reversal potentials under different Na-K gradients. When the pipette contained 155 mM K, single-channel currents had a slope conductance of 28 pS and a reversal potential of -4.3 mV. Baseline current levels often shifted in a negative direction during the application of ethanol, indicating a hyperpolarization of the membrane potential and an increase in channel activity.
Oleson
D R
DR
Department of Psychiatry and Behavioral Sciences, Emory University School of Medicine, Atlanta, Georgia 30306.
DeFelice
L J
LJ
Donahoe
R M
RM
D002478:Cells, Cultured; D000431:Ethanol / Q000494:pharmacology*; D006801:Humans; D007108:Immune Tolerance / Q000187:drug effects / Q000276:immunology; D008213:Lymphocyte Activation / Q000187:drug effects / Q000276:immunology; D008564:Membrane Potentials / Q000187:drug effects; D011188:Potassium / Q000378:metabolism*; D015221:Potassium Channels / Q000187:drug effects*; D013601:T-Lymphocytes / Q000187:drug effects* / Q000276:immunology
D015221:Potassium Channels; D000431:Ethanol; D011188:Potassium