Delayed rectifier K1 current of dog bronchial myocytes: effect of pollen sensitization and PKC activation
نویسندگان
چکیده
GARETH J. WALDRON,1 STEFAN B. SIGURDSSON,2 ERNESTO A. AIELLO,3 ANDREW J. HALAYKO,4 NEWMAN L. STEPHENS,4 AND WILLIAM C. COLE1 1Smooth Muscle Research Group, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1; 4Department of Physiology, Faculty of Medicine, University of Manitoba, Winnipeg, Manitoba, Canada R3T 2N2; 2Department of Physiology, Faculty of Medicine, University of Iceland, Reykjavik, Iceland IS-101; and 3Centro de Investigaciones Cardiovasculares, Facultad de Medicina, Universidad Nacional de La Plata, 1900 La Plata, Argentina
منابع مشابه
Delayed rectifier K+ current of dog bronchial myocytes: effect of pollen sensitization and PKC activation.
The properties of delayed rectifier K+ current [ I K(dr)] of canine airway smooth muscle cells isolated from small bronchi and its modulation by protein kinase C (PKC) were studied by whole cell patch clamp. I K(dr) activated positive to -40 mV, with half-maximal activation at -16 ± 1.2 mV ( n = 15) and average current density of 31 ± 2.6 pA/pF ( n = 15) at +30 mV. The capacitive surface area, ...
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Although inactivation of the rapidly activating delayed rectifier current (I(Kr)) limits outward current on depolarization, the role of I(Kr) (and recovery from inactivation) during repolarization is uncertain. To characterize I(Kr) during ventricular repolarization (and compare with the inward rectifier current, I(K1)), voltage-clamp waveforms simulating the action potential were applied to ca...
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OBJECTIVE The purpose of this study was to investigate the properties of the slow component of the delayed rectifier potassium current (I(Ks)) in myocytes isolated from undiseased human left ventricles. METHODS The whole-cell configuration of the patch-clamp technique was applied in 58 left ventricular myocytes from 15 hearts at 37 degrees C. Nisoldipine (1 microM) was used to block inward ca...
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