Ryanodine receptor adaptation: control mechanism of Ca(2+)-induced Ca2+ release in heart.
Adaptation of single cardiac ryanodine receptor (RyR) channels was demonstrated by application of the caged calcium ion (Ca2+) methodology. In contrast to conventional desensitization found in surface membrane ligand-gated channels, single cardiac RyR channels adapted to maintained Ca2+ stimuli, preserving their ability to respond to a second (larger) Ca2+ stimulus. RyR adaptation may represent a molecular control mechanism for smoothly graded Ca(2+)-induced Ca2+ release in heart and may be a fundamental feature of channels, including the inositol triphosphate receptor, that are involved in intracellular Ca2+ signaling in many cell types.
Györke
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S
Department of Physiology and Biophysics, University of Texas Medical Branch, Galveston 77555.
Fill
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D000222:Adaptation, Physiological; D000818:Animals; D002118:Calcium / Q000378:metabolism* / Q000494:pharmacology; D015220:Calcium Channels / Q000378:metabolism*; D004285:Dogs; D015544:Inositol 1,4,5-Trisphosphate / Q000378:metabolism; D053496:Inositol 1,4,5-Trisphosphate Receptors; D009124:Muscle Proteins / Q000378:metabolism*; D009206:Myocardium / Q000378:metabolism*; D010782:Photolysis; D011956:Receptors, Cell Surface / Q000378:metabolism; D018160:Receptors, Cytoplasmic and Nuclear; D019837:Ryanodine Receptor Calcium Release Channel
D015220:Calcium Channels; D053496:Inositol 1,4,5-Trisphosphate Receptors; D009124:Muscle Proteins; D011956:Receptors, Cell Surface; D018160:Receptors, Cytoplasmic and Nuclear; D019837:Ryanodine Receptor Calcium Release Channel; D015544:Inositol 1,4,5-Trisphosphate; D002118:Calcium