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Biomedical subjects

I M Shvetsov

Publications and source records attributed to I M Shvetsov.

15 recordsLinked to original sources
PubMed1989

[Modelling of ventricular tachycardia against a background of an elongated Q-T interval].

During the experiments on dogs we've created a mood of stable ventricular tachycardia induced by electrical stimulation of the left stellate ganglion at the elongated Q-T interval. The elongated cardiac systole--Q-T interval on ECG is induced by intravenous cesium chloride (l mmol/kg of dog's weight), which results in the disturbed myocardial electrolyte balance seen as tissue hypokalemia. In the dogs with electrical cardiac instability irritation of the left stellate ganglion resulted in polymorphic ventricular tachyarrhythmia in 83% of the animals. The created model has documented a role played by intracardiac pathology (electrolyte imbalance) in combination with the increased activity of the stellate ganglion in the mechanism of ventricular arrhythmia seen at the elongated Q-T interval.

Animals↗
PubMed1982

[Endogenous catecholamines and heart function in stimulation of the accelerator nerve].

The role of catecholamines in realization of the effects of the augmenting cardiac nerve has been studied during acute experiments on dogs anesthesized with hexenal. Activation of pump function and myocardial contractility during nerve stimulation has been shown to be in good agreement with the increased noradrenaline concentration in the coronary sinus blood. The synthesis of adrenaline has not been found to lag behind its consumption upon the exposure described. Nerve stimulation has led to accumulation of myocardial adrenaline which takes part in realization of a positive inotropic effect to a far less extent than noradrenaline, and exerts no adverse action on cardiac function.

Animals↗
PubMedDate not supplied

[Sympathetic innervation of the heart and long Q-T syndrome].

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.

Animals↗
PubMedDate not supplied

[Effect of sodium selenite and alpha-tocopherol on the microcirculation in massive blood loss in dogs].

Effect of little doses of sodium selenite combined with alpha-tocopherol on microcirculation was studied in experimental bloodletting in dogs. It was established that more rapid recovery, as compared to control, of blood flow in the visceral basin and more rapid elevation of arterial blood pressure after massive bloodletting occur following the pretreatment with sodium selenite at a dose of 30 micrograms/kg and alpha-tocopherol at a dose of 25 mg/kg. The blood flow gets recovered in small vessels (arterioles, vanules and capillaries) while in controls it recovers largely in greater vessels.

Animals↗