Voltage-dependent anion-selective channels in cultured smooth muscle cells of the rat aorta.
1. Properties of the voltage-dependent anion-selective channel in cultured smooth muscle cells of the rat aorta were studied using the patch-clamp technique. 2. The channel had a single channel conductance of 346 +/- 4 pS (n = 43, mean +/- SEM) with symmetrical 142 mM-Cl- solution in inside-out patch configurations. 3. The channel was activated spontaneously at a potential range -20 approximately +20 mV and inactivated more rapidly with increases to more positive or negative potentials. 4. The channel was selective for anions and the permeability ratio for monovalent anion was Br-:Cl-:HCOO-:CH3COO-:propionate-:aspartate- = 1.1:1:0.7:0.4: less than 0.02: less than 0.02. 5. The openings of the channels were observed more frequently in inside-out membrane patches than in cell-attached ones, and were independent of intracellular free Ca concentrations. 6. The density of this channel was estimated to be 1.3/micron2. 7. Physiological roles of the channel were discussed.
Sadoshima
J
J
Research Institute of Angiocardiology, Faculty of Medicine Kyushu University, Fukuoka, Japan.
Akaike
N
N
Tomoike
H
H
Kanaide
H
H
Nakamura
M
M
D000818:Animals; D000838:Anions / Q000378:metabolism*; D001011:Aorta / Q000166:cytology / Q000378:metabolism; D002478:Cells, Cultured; D002712:Chlorides / Q000378:metabolism; D004553:Electric Conductivity; D004594:Electrophysiology; D007473:Ion Channels / Q000378:metabolism / Q000502:physiology*; D007700:Kinetics; D009131:Muscle, Smooth, Vascular / Q000166:cytology / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D000838:Anions; D002712:Chlorides; D007473:Ion Channels