• 1 January 1978
    • journal article
    • research article
    • Vol. 20  (2) , 317-329
Abstract
Creatine kinase efflux from isolated mouse skeletal muscle was monitored in the presence of various concentrations of Ca2+ or La3+ for 5 h. Ca2+ levels (10-3 to 10-2 M) augmented enzyme leakage to greater than 300% above control. La3+, which may displace Ca2+ from sarcolemmal and t[transverse]-tubule membranes, depressed enzyme efflux at concentrations between 10-5 to 10-3 M. Extracellular Ca2+ mediates in vitro enzyme efflux and may act on the sarcolemma and its extensions. The regulation of enzyme leakage in various muscle disorders was discussed.