Whole-cell K+ currents in isolated rabbit corneal epithelial cells.
Membrane currents were recorded from enzymatically isolated cells from basal layers of rabbit corneal epithelium by the whole-cell clamp technique. Pipettes contained 140.4 mM KCl and extracellular K+ concentration was varied. The membrane currents on step voltage changes were rectangular currents with some fluctuations. The fluctuations disappeared near the zero-current potential. The reversal potential in normal Tyrode's solution with 5.4 mM K+ was -57.8 +/- 6.2 mV (mean +/- S.D., n = 10). Increasing [K+]o from 5.4 to 140.4 mM shifted the reversal potentials in the positive direction with a slope of 41.0 mV/decade. Concomitant depolarization of the resting potential was observed on increasing [K+]o. The whole-cell currents were blocked by Cs+ or Ba2+. These suggest that the major current component in the corneal epithelial cells in K+.
Tantirittisak
W
W
Department of Physiology, Juntendo University School of Medicine, Tokyo, Japan.
Ochi
R
R
Kanai
A
A
D000818:Animals; D003315:Cornea / Q000166:cytology / Q000378:metabolism*; D004847:Epithelial Cells; D004848:Epithelium / Q000378:metabolism; D066298:In Vitro Techniques; D008564:Membrane Potentials; D011188:Potassium / Q000378:metabolism*; D015221:Potassium Channels / Q000378:metabolism; D011817:Rabbits
D015221:Potassium Channels; D011188:Potassium