Evidence for novel caffeine and Ca~2+ binding sites on the lobster skeletal ryanodine receptor

摘要

1. The effects of Ca~2+, ATP and caffeine on the gating of lobster skeletal muscle ryanodine receptors (Ryr) was investigated after reconstitution of the channels into planar phospholipid bilayers and by using [~3H]-ryanodine binding studies. 2. The single channel studies reveal that the EC_50 (60 uM) for activation of the lobster skeletal RyR by Ca~2+ as the sole ligand is higher than for any other isoform of RyR studied.