Methylxanthine-Induced Escalation: A Propagated Wave Phenomenon Observed in Skeletal Muscle Developing in Culture

摘要

Relatively low concentrations of methylxanthines increase spontaneous twitching in cultured muscle fibers; they also cause a second activity, escalation, which is the initiation and undiminished propagation of visible waves. The effect on twitching is abolished by depolarizing concentrations of K⁺ or by tetrodotoxin; the effect on escalation is not. Escalation is prevented by removal of external Ca⁺⁺ or by the addition of tetracaine.