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Updated: Apr 27, 2026

Contractility Measurements on Isolated Papillary Muscles for the Investigation of Cardiac Inotropy in Mice
Published on: September 17, 2015
[Contractile functions of myocardium and their regulation]
Abstract:
Myocardial contractility is the ability of the cardiac muscle to contract, thereby generating force. Contractile functions of the myocardium are influenced by a number of intrinsic and extrinsic factors. The intrinsic factors, including the initial length of the muscle fibers, stimulation frequency and cardiac rhythm are modulated by neurohumoral mechanisms and extrinsic factors (ions and energy balance, temperature, pH, drugs, etc.). The mechanism of the cardiac contraction, intrinsic and neurohumonal regulation of the cardiac activity and changes in contractile functions of the myocardium and their regulation under pathological conditions are described in this article.
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