[Repolarization of canine ventricular myocardium under the supraventricular rhythm].

The ventricular myocardium is characterized by heterogeneity of activation-recovery interval durations. The transmural ARI gradients are present in the right ventricular apex (ARIs monotonically decreased as one moved from the endocardium to the epicardium), and in the left ventricular base (repolarization in the subepicardial layers was significantly shorter than that in the midmyo cardial layers whereas subendocardial ARIs did not differ from the others). The repolarization pattern of these myocardial regions is governed by the distribution of ARIs.

[Reflection of distribution of the epicardial ventricular potential on the dog body surface during electrical stimulation of the myocardium].

Electrical pacing of the apex, base, and free wall of the heart right and left ventricles, as well as the left ventricle's interventricular septum revealed that localisation of the ectopic focus determined the sequence of ventricular depolarisation, the site formation, and the pathway of displacement of the areas' positive and negative potentials and their extrema on the thoracic surface. Time of the mutual movement (inversion) of positive and negative zones on the body surface was found to depend on the pacing site in the wall of ventricles.

[The role of ketone bodies in the development of postalcoholic-intoxication heart damage in rats].

Experiments on rats subjected to forced alcoholization for 5.5 days were made to measure the content of ethanol, acetaldehyde and ketone bodies in the blood during intoxication and 2 days after ethanol withdrawal and to estimate the intensity of postintoxication disorders in heart activity on the third day after alcoholization withdrawal. A positive correlation was discovered between depression of left ventricular contractility and the blood content of acetaldehyde and ketone bodies.

[The relation of abstinence analgesia to the development of cardiac disorders in the ethanol withdrawal syndrome in rats].

Ethanol was administrated intragastrically (25%, w/v) to Wistar male rats. They received 7-10 g ethanol/kg b.wt.

[Myocardial damage and the sympatho-adrenal system in ethanol abstinence syndrome in rats].

Increase in content of II-oxycorticosteroids and in activity of dopamine-beta-hydroxylase in blood serum, decrease in concentration of adrenaline in adrenal glands with simultaneous accumulation of the catecholamine in myocardium were observed in rats after intensive alcoholization within 5 days (intragastric administration of ethanol 4-5 g/kg twice daily). In this case content of noradrenaline and its density in the catecholamine-containing nervous fibers were decreased. Ethanol abolishing, as shown by dynamics of catecholamines in heart and adrenal glands, caused an additive stimulation of the sympathoadrenal system, which reached the maximal level within a day and accomplished within 3 days after the last ethanol injection.

[Ethanol withdrawal syndrome in the pathogenesis of alcoholic heart damage].

In an ultrastructural and functional study of rat hearts, some animals had received liquid food containing ethanol (36.1% of total caloric intake) for 14 weeks (group 1); in half of the rats (group 2), ethanol-containing diet was at regular intervals replaced by an alcohol-free diet (five three-day cycles). Animals on dry forage and water or ethanol-free liquid diet were taken as controls.

[Pharmacologic analysis of the role of catecholamines in the mechanism of alcoholic affection of the heart].

The authors studied the effect of 6-oxidopamine and rausedyl on the manifestation of cardiac disorders in rats given 3-5 g/kg ethanol by way of the stomach at 12-hour intervals for 5.5 days. 6-oxidopamine was injected intraperitoneally in a dose of 50 mg/kg 24 hours before the beginning of alcoholization and one hour after the first administration of ethanol.

[Determination of the leading factors in the pathogenesis of an alcoholic lesion of the heart].

Male rats were given per os 25% ethanol solution twice a day at 9.00 and 21.00 for 5.

Morphofunctional examination of the heart in rats with the alcohol withdrawal syndrome.

Using histochemical methods, light and electron microscopy, authors examined rat heart 2-6 hours, 1, 3, and 7 days after discontinuation of forced intoxication with alcohol. At the same time, they assessed the contractile function and creatine phosphokinase (CPK) activity in the isolated perfused heart, and the development of animal destruction. Ethanol withdrawal was followed by escalation of vascular disorders in the heart, dystrophic changes in the subcellular structures, considerable polymorphism in enzyme distribution and activity, and formation of foci containing disintegrating myocytes with contractures.

[Participation of catecholamines in the mechanism of heart damage during the alcohol withdrawal syndrome in rats].

Withdrawal syndrome in rats was induced after ethanol administration in a dose of 4-5 g/kg b. w. twice daily for 5 consecutive days.

[Cardiac effects of insulin in ethanol intoxication and in the postintoxication period].

Insulin (2 IU/ml) effect on the contractile function, glucose consumption and lactate release by the myocardium was studied in experiments on the isolated rat heart performed at different time after a single (8 g/kg) and 10-fold with a 12-hour interval (8-10 g/kg) intragastric administration of ethanol. A single administration of ethanol failed to influence the contractile function, glucose consumption and lactate release by the isolated heart. The magnitude of a positive inotropic reaction to insulin increased and its stimulating effect on glucose utilization by the myocardium weakened.

[Contractile function, glucose consumption and lactate release by the isolated rat heart during different regimens of alcohol administration and after discontinuation of ethanol].

Acute or chronic intoxication of rats with ethanol (intragastric administration at a dose of 8 g/kg or free-choice drinking of 10% ethanol for 3 months) produced no significant changes in contractile function, glycogen content, glucose uptake and lactate release in isolated hearts. Withdrawal syndrome simulated in rats following a short period of severe intoxication with ethanol at a dose of 4-5 g/kg twice daily has demonstrated a 15 and 28% decrease in peak systolic pressure and tension time index, respectively. In this case glucose uptake and lactate release were 2 times higher.

[Comparative characteristics of voluntary and semivoluntary methods of the alcoholization of rats].

Water and ethanol consumption, blood and urine ethanol concentrations were measured in male rats aged 1.5 to 8 months. The animals had ethanol solutions (5-25%) and water as alternate fluid (two-bottle choice) or a 10% ethanol solution as a sole water source.

[Catecholamines in the mechanism of the cardionecrotic action of acetaldehyde].

Administration of acetaldehyde to rats by inhalation or intraperitoneally (in repeated doses) provokes an emergence of micronecroses in the myocardium. Administration of acetaldehyde in a dose causing no injury to the myocytes potentiates the cardionecrotic action of adrenalin. Pretreatment with L-DOPA potentiates while that of L-alpha-methyl-DOPA or alpha-methyl-p-tyrosine averts the necrosogenous action of acetaldehyde.