H2O2 activates ryanodine receptor but has little effect on recovery of releasable Ca content after fatigue
نویسندگان
چکیده
TOSHIHARU OBA,1 CHIEKO KURONO,2 RITSUKO NAKAJIMA,3 TETSUO TAKAISHI,4 KAZUTO ISHIDA,5 GERALDINE A. FULLER,6 WUTHICHAI KLOMKLEAW,6 AND MAMORU YAMAGUCHI6 1Departments of Regulatory Cell Physiology, and 2Morphological Anatomy, Graduate School of Medical Sciences, 3Nagoya City University School of Nursing, 4Department of Health Science, Institute of Natural Sciences, Nagoya City University, Nagoya 467-8601; 5Department of Physical Therapy, Nagoya University School of Health Sciences, Nagoya 461-8673, Japan; and 6Department of Veterinary Biosciences, College of Veterinary Medicine, The Ohio State University, Columbus, Ohio 43210
منابع مشابه
H2O2 activates ryanodine receptor but has little effect on recovery of releasable Ca2+ content after fatigue.
We studied whether hydrogen peroxide (H(2)O(2)) at </=10 microM activates the ryanodine receptor and decreases releasable Ca(2+) content in the sarcoplasmic reticulum after fatigue. Exposure of rabbit or frog skeletal muscle ryanodine receptors to 10 microM H(2)O(2) enhanced channel activity in lipid bilayers when the redox potential was defined at cis = -220 mV and trans = -180 mV. Channel act...
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Oxidative stress may contribute to cardiac ryanodine receptor (RyR2) dysfunction in heart failure (HF) and arrhythmias. Altered RyR2 domain-domain interaction (domain unzipping) and calmodulin (CaM) binding affinity are allosterically coupled indices of RyR2 conformation. In HF RyR2 exhibits reduced CaM binding, increased domain unzipping and greater SR Ca leak, and dantrolene can reverse these...
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Diastolic waves of Ca(2+) release have been shown to activate delayed afterdepolarizations as well as some cardiac arrhythmias. The aim of this study was to investigate whether increasing ryanodine receptor open probability alone or in the presence of beta-adrenergic stimulation produces diastolic Ca release from the sarcoplasmic reticulum (SR). When voltage-clamped rat ventricular myocytes wer...
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This review discusses the control of the amplitude of the cardiac systolic Ca transient. The Ca transient arises largely from release from the sarcoplasmic reticulum (SR). Release is triggered by calcium-induced calcium release (CICR) whereby the entry of a small amount of Ca on the L-type Ca current, "the trigger", results in the release of much more Ca from the SR. There are three potential c...
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AIMS Most of the calcium that activates contraction is released from the sarcoplasmic reticulum (SR) through the ryanodine receptor (RyR). It is controversial whether activators of the RyR produce a maintained increase in the amplitude of the systolic Ca transient. We therefore aimed to examine the effects of activation of the RyR in large animals under conditions designed to be as physiologica...
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