Activity of single potassium channels recorded from single isolated visceral and vascular smooth muscle cells
Relaxation of smooth muscle implies some existing tension. This is present presumably because the internal free ionised calcium concentration [Ca2+]; exceeds some threshold level causing activation of the myosin light chain kinase or leiotonin systems and actin-myosin interaction (Perry & Grand, 1979; Hartshorne, 1981). Relaxation of this existing tension may surely occur in a wide variety of ways; one obvious possibility is that [Ca2+]i is reduced and, probably after a slight delay, tension then declines.
KeywordsMyosin Light Chain Kinase Membrane Patch Physiological Salt Solution Rabbit Jejunum Action Potential Discharge
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