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Updated: Feb 11, 2026

Mechanical Control of Relaxation Using Intact Cardiac Trabeculae
Published on: February 17, 2023
[The calcium pump in the sarcolemma controls smooth muscle relaxation]
Abstract:
In order to identify the functional role of the sarcolemma calcium pump in the control over smooth muscle relaxation there was studied the effect of temperature on relaxation kinetics of myometrium carbachol contracture, actomyosin superprecipitation isolated from this object and Mg2+, ATP-dependent transport of Ca2+ in the fraction of uterus sarcolemma vesicles. The activation energies of the processes under study were determined in comparison. It was concluded from the evidence obtained that relaxation of the smooth muscle contracture is controlled by the stimulated temperature increase and by Na(+)-independent trans-sarcolemma release of Ca2+ from the myocytes sensitive to La3+ effect. The release is provided by the calcium pump of the plasmic membrane.
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