An acetazolamide-sensitive inward chloride pump in vascular smooth muscle.
In smooth muscle cells, which have a small but significant chloride ion permeability, Cl:HCO3 exchange and (Na+K+Cl) cotransport are known to act as inwardly directed chloride pumps. However, even allowing for overestimation of [Cl]i due to intracellular interference with the Cl-recording electrodes, there remained a residual accumulation of chloride in rat arterial smooth muscle under conditions in which neither of these processes is operative. Manipulation of [Cl]i and Cl permeability using pharmacological agents whilst monitoring both Em and [Cl]i showed that an acetazolamide-sensitive mechanism, perhaps a Cl-dependent ATPase, is the third pathway for Cl accumulation.
Chipperfield
A R
AR
Department of Anatomy and Physiology, University of Dundee, UK.
Davis
J P
JP
Harper
A A
AA
D000086:Acetazolamide / Q000494:pharmacology*; D000818:Animals; D002034:Bumetanide / Q000494:pharmacology*; D018118:Chloride Channels; D002712:Chlorides / Q000378:metabolism*; D005263:Femoral Artery / Q000187:drug effects / Q000502:physiology*; D066298:In Vitro Techniques; D007473:Ion Channels / Q000502:physiology*; D007700:Kinetics; D008297:Male; D008565:Membrane Proteins / Q000187:drug effects / Q000502:physiology*; D009131:Muscle, Smooth, Vascular / Q000187:drug effects / Q000502:physiology*; D009579:Nitrobenzoates / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013997:Time Factors
D018118:Chloride Channels; D002712:Chlorides; D007473:Ion Channels; D008565:Membrane Proteins; D009579:Nitrobenzoates; D002034:Bumetanide; C058176:5-nitro-2-(3-phenylpropylamino)benzoic acid; D000086:Acetazolamide