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Updated: Sep 9, 2026

Electrocardiogram Recordings in Anesthetized Mice using Lead II
Published on: June 20, 2020
[Sympathetic innervation of the heart and long Q-T syndrome]
Abstract:
The effect of stimulation of the right sympathetic augmenting nerve of the heart on myocardial electrical activity and central hemodynamic values was studied in experiments on intact and stellectomized dogs. Prevailing tonus of the right augmenting nerve resulting from its stimulation was attended by ischemic changes of the myocardium and moderate lengthening of the Q-T interval in intact dogs. Increased rate of cardiac contractions and rise of arterial pressure in stellectomized dogs as well as tachycardia occurring in them due to stimulation of the nerve bore evidence of increased sensitivity of beta-adrenoreceptors in the partly denervated heart. The authors show the role of asymmetry of the sympathetic nerve regulation, caused by unilateral stimulation of the augmenting nerve, in combination with changed sensitivity of the myocardial adrenergic receptors in the development of the lengthened Q-T interval syndrome.
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