[The cardioprotective action of quercetin in experimental occlusion and reperfusion of the coronary artery in dogs].

In experimental myocardial infarction in dogs caused by 60-minute occlusion of the coronary artery with the subsequent 24-hour reperfusion, the administration of quercetin solution (50 mg/kg) was found to improve the contractile function of the left ventricular myocardium, to decrease the incidence of heart rate and conductivity disorders, to contribute to limitation of the ischemic damage area, to exert the protective effect on the ultrastructure of the coronary arteries that can promote the preservation of the vessels' integrity, the improvement of the coronary circulation and the prevention of intravascular thrombus formation.

[The effect of leukotriene LTC4 on the coronary vascular bed and on myocardial contractile function].

The effects of intracoronary LTC4 administration have been studied in narcotized dogs with an intact chest. LTC4 in doses of 0.5-40 micrograms produced a dose-dependent decrease in coronary flow, inhibition of myocardial contractility and disturbance of cardiac rhythm.

[The effect of the 5-lipoxygenase inhibitor quercetin on the functional and morphologic manifestations of myocardial lesions in ischemia and reperfusion of the heart].

In experimental canine myocardial infarction induced by an hour coronary artery occlusion, followed by 5-hour reperfusion, quercetin solution, 10 mg/kg, was demonstrated to improve left ventricular myocardial contractility, to reduce the incidence of rhythm and conduction disturbances, to promote the limitation of an ischemic lesion area, to produce a protective effect on the ultrastructure of coronary artery, contributing to the maintenance of vessel integrity, improvement of coronary blood flow, and prevention of intravascular thrombus formation.

[Contractility of the right ventricle and pulmonary circulation pressure in young sportsmen].

The paper presents some data on the structure of the systole of the right ventricle obtained by means of kinetocardiography in 280 sportsmen, aged 12-14 years, with different functional states of their organisms (non-trained, poorly and well-trained, with chronic overstraining of the heart), as well as some data on the level of the systolic pressure in the pulmonary circulation system (by the Buzstin method) at rest and during the restorative period after exercises (test of the Leningrad Institute of Physical Culture, bycycle tests). The more the organism is trained, the more distinct the stages ofthe syndrome of regulated myocardial hypodynamia were found to be, a moderate hyperfunctionof the heart is noted during physical exercises that is accompanied by slight elevations of the pressure in the pulmonary system. In cases of chronic cardiac overstraining myocardial hypodynamia, stage I--II, was found, pressure elevation in the pulmonary circulation system -- in 21.