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Updated: Apr 16, 2026

Contractility Measurements on Isolated Papillary Muscles for the Investigation of Cardiac Inotropy in Mice
Published on: September 17, 2015
[Inotropic effect of a new probiotic product on myocardial contractility. Comparison with diazoxide]
Abstract:
The inotropic effect of a new probiotic product on myocardial contractility of the frog Rana ridibunda and the effect of probiotic product on the rat cardiac mitochondria swelling were studied. In both cases, the comparison with known cardioprotector diazoxide was done. Probiotic product and diazoxide were shown to cause a dual effect on the maximum force induced by the muscle sample during spontaneous atrial contraction. Addition of agents caused a negative impact, while washing out exerted a positive inotropic effect. At the same time probiotic product has virtually no effect on the amplitude of contraction induced by electrical stimulation of the ventricle fragments. Probiotic product decreases both proton passive permeability in the inner mitochondrial membrane, and potassium active transport in mitochondria caused by activation of K(+)-uniporter of cardiomyocytes. A possible mechanism of action of probiotic product is discussed.
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