Determination of Na+/Cl-, Na+/HCO3- and Na+/K+/2Cl- co-transporter activity in corneal endothelial cell plasma membrane vesicles.
Corneal endothelial cell derived plasma membrane vesicles were used to investigate the presence of Na+/Cl-, Na+/HCO3- and Na+/K+/2Cl- co-transporter activity in the plasma membranes of these cells. Na+/H+ exchange was blocked by the presence of 1 mM amiloride in all determinations. The rate of accumulation of Na+ in the presence of chloride or bicarbonate was not significantly different from its accumulation in the presence of acetate, thiocyanate or gluconate. The addition of K+ to Na+ plus Cl- did not stimulate Na+ accumulation into the vesicles. The present work provides no evidence for Na+/K+/2Cl-, Na+/Cl- or Na+/HCO3- co-transport in corneal endothelial cell plasma membrane vesicles.
Lane
J R
JR
Department of Optometry and Vision Sciences, Cardiff University of Wales, UK.
Wigham
C G
CG
Hodson
S A
SA
D000818:Animals; D001639:Bicarbonates / Q000378:metabolism*; D001692:Biological Transport; D002352:Carrier Proteins / Q000378:metabolism*; D002417:Cattle; D002712:Chlorides / Q000378:metabolism; D004728:Endothelium, Corneal / Q000166:cytology / Q000378:metabolism*; D011188:Potassium / Q000378:metabolism; D012964:Sodium / Q000378:metabolism*; D049992:Sodium Chloride Symporters; D027982:Sodium-Bicarbonate Symporters; D028021:Sodium-Potassium-Chloride Symporters; D027981:Symporters
D001639:Bicarbonates; D002352:Carrier Proteins; D002712:Chlorides; D049992:Sodium Chloride Symporters; D027982:Sodium-Bicarbonate Symporters; D028021:Sodium-Potassium-Chloride Symporters; D027981:Symporters; D012964:Sodium; D011188:Potassium