Effects of local anesthetics on single channel behavior of skeletal muscle calcium release channel

A study was conducted on the effects of tetracaine, procaine and QX314 on Ca2+ release by the sarcoplasmic reticulum (SR). Purified skeletal muscle Ca2+ release channel complex was incorporated into planar lipid bilayers and examined. Results indicate adding tetracaine andprocaine to the bilayer's cytoplasmic side or SR lumenal side caused a reduction in the activity of Ca2+- and ATP-gated channels. Both drugs inhibitedchannel activity through binding with at least two cooperativelty interacting high-affinity regulatory sites of the SR Ca2+ release channel.