Role of Cl- current in endothelin-1-induced contraction in rabbit basilar artery.
Cl- efflux induces depolarization and contraction of smooth muscle cells. This study was undertaken to explore the role of Cl- channels in endothelin-1 (ET-1)-induced contraction in rabbit basilar artery. Male New Zealand White rabbits (n = 26), weighing 1.8-2.5 kg, were euthanized by an overdose of pentobarbital. The basilar arteries were removed for isometric tension recording. ET-1 produced a concentration-dependent contraction of the rabbit basilar artery in the normal Cl- Krebs-Henseleit bicarbonate buffer (123 mM Cl-). The ET-1-induced contraction was reduced by the following manipulations: 1) inhibition of Na+-K+-2Cl- cotransporter with bumetanide (3 x 10(-5) and 10(-4) M), 2) bicarbonate-free solution to disable Cl-/HCO exchanger, and 3) preincubation of rings with the Cl- channel blockers niflumic acid, 5-nitro-2-(3-phenylpropylamino)benzoic acid, and indanyloxyacetic acid 94. The ET-1-induced contraction was enhanced by substitution of extracellular Cl- (10 mM) with methanesulfonic acid (113 mM). Cl- channels are involved in ET-1-induced contraction in the rabbit basilar artery.
Dai
Y
Y
Department of Neurosurgery, University of Mississippi Medical Center, Jackson, Mississippi 39216, USA.
Zhang
J H
JH
D020533:Angiogenesis Inhibitors / Q000494:pharmacology; D000818:Animals; D001488:Basilar Artery / Q000502:physiology*; D002021:Buffers; D002034:Bumetanide / Q000494:pharmacology; D002118:Calcium / Q000494:pharmacology; D018118:Chloride Channels / Q000378:metabolism; D027963:Chloride-Bicarbonate Antiporters / Q000378:metabolism; D002712:Chlorides / Q000378:metabolism*; D016861:Cyclooxygenase Inhibitors / Q000494:pharmacology; D004232:Diuretics / Q000494:pharmacology; D019332:Endothelin-1 / Q000494:pharmacology*; D006016:Glycolates / Q000494:pharmacology; D006531:HEPES / Q000494:pharmacology; D008297:Male; D009131:Muscle, Smooth, Vascular / Q000378:metabolism; D009544:Niflumic Acid / Q000494:pharmacology; D009579:Nitrobenzoates / Q000494:pharmacology; D011817:Rabbits; D049994:Sodium Potassium Chloride Symporter Inhibitors; D028021:Sodium-Potassium-Chloride Symporters / Q000378:metabolism; D014661:Vasoconstriction / Q000187:drug effects* / Q000502:physiology
D020533:Angiogenesis Inhibitors; D002021:Buffers; D018118:Chloride Channels; D027963:Chloride-Bicarbonate Antiporters; D002712:Chlorides; D016861:Cyclooxygenase Inhibitors; D004232:Diuretics; D019332:Endothelin-1; D006016:Glycolates; D009579:Nitrobenzoates; D049994:Sodium Potassium Chloride Symporter Inhibitors; D028021:Sodium-Potassium-Chloride Symporters; D002034:Bumetanide; C058176:5-nitro-2-(3-phenylpropylamino)benzoic acid; D009544:Niflumic Acid; C015765:MK 473; D006531:HEPES; D002118:Calcium