Activation of the skeletal muscle Ca2+ release channel by the triazine dyes cibacron blue F3A-G and reactive red 120.
Vesicle-45Ca2+ ion flux and planar lipid bilayer single-channel measurements have shown that the Ca2+ release channel of skeletal muscle sarcoplasmic reticulum (SR) is activated by micromolar concentrations of Cibacron Blue F3A-G (Reactive Blue 2) and Reactive Red 120. Cibacron Blue increased the 45Ca2+ efflux rate from heavy SR vesicles by apparently interacting with both the adenine nucleotide and caffeine activating sites of the channel. Dye-induced 45Ca2+ release was inhibited by Mg2+ and ruthenium red. In single channel recordings with the purified channel protein complex, Cibacron Blue increased the open time of the Ca2+ release channel without an apparent change in the conductance of the main and subconductance states of the channel.
Xu
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L
Department of Biochemistry, University of North Carolina, Chapel Hill 27599-7260.
Jones
R V
RV
Meissner
G
G
D000225:Adenine / Q000494:pharmacology; D000818:Animals; D002110:Caffeine / Q000494:pharmacology; D015220:Calcium Channels / Q000187:drug effects / Q000378:metabolism*; D002132:Calcium Radioisotopes / Q000378:metabolism; D004396:Coloring Agents; D008274:Magnesium / Q000502:physiology; D009132:Muscles / Q000187:drug effects / Q000378:metabolism*; D011817:Rabbits; D012430:Ruthenium Red / Q000494:pharmacology; D012519:Sarcoplasmic Reticulum / Q000378:metabolism; D014227:Triazines / Q000494:pharmacology*
D015220:Calcium Channels; D002132:Calcium Radioisotopes; D004396:Coloring Agents; D014227:Triazines; D012430:Ruthenium Red; D002110:Caffeine; C012842:Cibacron Blue F 3GA; C042516:reactive red 120 dye; D008274:Magnesium; D000225:Adenine