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Updated: Mar 1, 2026

Isolation of Atrial Myocytes from Adult Mice
Published on: July 25, 2019
[Comparative characteristics of the mechanical activity of atria and ventricles]
Abstract:
Differences between parameters of isometric and isotonic contractions of atria and ventricles were studied in warm-blooded and cold-blooded animals. The maximal shortening velocity of contractile element was determined from isometric contraction using a two-component Hill's model as well as from the strength-velocity ratio. The atrial Vmax was about twice as high as that of ventricles. The rate constant of delayed activation in atrium was 10.6 +/- 0.4 s-1, in the rabbit ventricles 4.42 +/- 0.60 s-1. The data suggest differences of ATP hydrolysis velocity with actomyosin ATP-ase of atrium and ventricles.
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