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Published on: May 7, 2020
Rapid myosin phosphorylation transients in phasic contractions in chicken gizzard smooth muscle
Abstract:
In intact smooth muscle strips from chicken gizzard, electrical stimulation and carbachol elicited brief, phasic contractions which were associated with a very rapid, transient phosphorylation of the 20 kDa myosin light chains. The phosphorylation transients reached their peak after 3 s and 6 s and preceded that of force. Phosphorylation was not significantly different from basal levels after 10 s and 30 s while force still amounted to 50% of the peak value. The rate of tension decline could be increased by cessation of stimulation or by addition of atropine, even at apparently basal phosphorylation levels suggesting a phosphorylation independent regulation.
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