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Contractility Measurements on Isolated Papillary Muscles for the Investigation of Cardiac Inotropy in Mice
Published on: September 17, 2015
Ventricular myosin of the shrew Crocidura russula, correlation with contractile properties
G Kessler-Icekson1, H Schlesinger, J J Leger
1Rogoff Medical Research Institute, Beilinson Medical Center, Petah Tikva, Israel.
Abstract:
The present study demonstrates that in the shrew ventricular muscle the speed of tension development and relaxation, as well as twitch duration, are much shorter than in the guinea-pig. It also shows that ventricular myosin of the shrew has a high Ca2+-activated ATPase activity and that it is composed of alpha-type heavy chains. Namely, the native molecule is a V1 variety of myosin. These findings advance our knowledge on an as yet uncharacterized mammalian heart and further demonstrate the correlation between mechanical properties and myosin type in heart muscle.
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