[The role of the lungs in regulating the generation of active forms of oxygen by the phagocytes, the concentration of immunoglobulins and the complement activity]. / Rol' legkikh v reguliatsii generatsii aktivnykh form kisloroda fagotsitami, soderzhaniia immunoglobulinov i aktivnosti komplementa.

Experiments on 25 intact dogs, 2 calves and clinical tests in 45 patients have shown that in the blood of the aorta or pulmonary vein leaving the lungs there is a rise in generation of active oxygen forms by leukocytes, their phagocytic activity, the activity of myeloperoxidase, NADPN-oxidase, complement, immunoglobulins content. As to the liver, kidneys, spleen, no such increased generation of active oxygen forms by leukocytes was registered. The results suggest an important role of the lungs in regulation of free radical activity of leukocytes, their phagocytic ability and thus in anti-infection defense of the body.

[Study of contractile properties of muscles of curarized animals by the method of stimulation impedancography]. / Issledovanie sokratitel'nykh svoistv myshts kurarizirovannykh zhivotnykh metodom stimuliatsionnoi impedansografii.

The effect of relaxation doses of tubocurarine on the stimulation and contractile properties of muscles in complete synaptic block was studied in experiments on laboratory rats by means of a previously developed method of stimulation impedancography. During intramuscular electrostimulation the stimulus threshold for short 0.01 mc test impulses increased, while the steepness of the characteristic "force of action--contractile effect" curve, registered at 1 mc impulses, reduced. The reduction was caused by loss of the function of synaptic nerve structures which take part in recruiting the contractile elements. Nonsynaptic mechanisms of recruiting through direct stimulation of the muscle fibres ensure 45% of recruitment. Changes of the duration of the contraction were not detected in the first 20 minutes of the effect. After 60-80 minutes of relaxation there was a tendency to prolongation of the time of the contraction act, which may be caused by prolonged immobilization of the animals.

The mechanisms of free-radical lipids and antioxidant heart protection in experimental ischaemia and infarction.

Free-radical lipid peroxidation (FRLP) during experimental myocardial ischaemia and infarction was studied on the first author's model using coronary occlusion in more than 1500 albino rats. FRLP was tested at various intervals after coronary occlusion (from the 20th minute to 14--30 days) in myocardial lipid extracts using various methods: 1) chemiluminescent method determining the intensity of free radical reactions, 2) diene conjugate production, 3) malone dialdehyde reaction, 4) Schiff bases fluorometric determination. The severity of ischaemia and infarction was assessed according to electrocardiographic, light and electron microscopic findings and morphometry of the damaged area. Intensified FRLP was registered in all four indicators at most tests performed within the first 14 days after production of ischaemia and infarction. The severity of ischaemic lesion could be reduced by FRLP inhibition using antioxidative agents of sharply differing chemical nature (sodium selenite, alpha-tocopherol a.o.). The authors conclude that FRLP intensification plays a role in the pathogenesis of myocardial ischaemia and infarction, and recommend to include antioxidative drugs in comprehensive heart protection.

[Role of the lungs in the regulation of the generation of active oxygen forms by leukocytes under normal and pathological conditions]. / O roli legkikh v reguliatsii generatsii aktivnykh form kisloroda leikotsitoami v norme i patologii.

Studies conducted in the clinic (in patients with cardiac diseases) and experiments (performed on intact dogs) by means of the hemiluminescent method and the nitroblue tetrazolium test showed that the lungs, in distinction to other organs (heart and others), have a stimulating effect on the generation of active oxygen forms (AOF) by the leukocytes. In this way the lungs may probably play a double role in the organism: potentiate its defence (by intensifying the microbicidal activity of the phagocytes) and facilitate damage (by secretion of AOF by the phagocytes beyond them--into the tissues); the resultant effect depends on the balance of these two types of action. In carcinoma of the lung the stimulating effect of its involved lobe (part) on the leukocytes diminishes.

[Acid hydrolase activity and cyclic nucleotide contents in the rat heart during myocardial ischemia and postischemic reperfusion]. / Aktivnost' kislykh gidrolaz i soderzhanie tsiklicheskikh nukleotidov v serdtse krys pri ishemii miokarda i v period postishemicheskoi reperfuzii.

The acid phosphatase and cathepsin D activities and cAMP and cGMP levels in isolated perfused rat heart were investigated during various periods of ischaemic myocardial injury and postischaemic reperfusion. The effect of phosphodiesterase inhibitor--caffeine was also studied. Free acid hydrolases activities and cyclic nucleotide content were increased under 40 and 60 min ischemia and 20 min postischaemic reperfusion. Addition of 50 microM caffeine to perfusion solution after 30 min of ischaemia resulted in increase of cAMP level, cAMP/cGMP ratio, lysosomal bound activities of acid hydrolase and decrease of free acid hydrolase activities. The obtained results suggested that defect in cAMP synthesis might be present in lysosomal membranes labilization in cardiomyocytes injured during ischaemic conditions. Addition of such agents, as caffeine, which increased heart cAMP level, may be effective in lysosomal membranes stabilization under reversible heart ischaemia and reperfusion.

[The generation of active microbicidal forms of oxygen by leukocytes transiting the vascular bed of the lungs]. / Generatsiia aktivnykh mikrobotsidnykh form kisloroda leikotsitami pri prokhozhdenii cherez sosudistoe ruslo legkikh.

In experiments on dogs using the chemiluminescent method and nitroblue-tetrazole reaction the authors found out that leucocytes while passing through the pulmonary vessels bed, in contrast to the spleen increase the generation of active microbicidal forms of oxygen. Due to this fact we suppose that the lungs may take part in the formation of free radical status and phagocytic antiinfectious defence of the organism.

[Effect of atenolol, dibunol, peroxidase and Astragalus dasynthus on the morphometric parameters of myocardial infarction]. / Vliianie atenolola, dibunola, peroksidazy i astragala pestrogo na morfometricheskie pokazateli infarkta miokarda.

Experiments were carried out on rats after coronary arterial ligation. In the myocardial infarction region there is the border zone or reversibly damaged zone which may be partially saved from necrosis by using beta-blocking agents. Atenolol, dibunol, Astragalus dasyanthus pall. moderately decrease the myocardial damage area at permanent and transient ischemia.

[Myocardial function and reactivity in thyrotoxicosis and in the post-thyrotoxic state (experimental-clinical study)]. / Funktsiia i reaktivnost' miokarda pri tireotoksikoze i v posttireotoksicheskom sostoianii (éksperimental'no-klinicheskoe issledovanie).

A response of the heart to hypoxia was studied in experimental thyrotoxicosis and physical exercise in patients with the thyrotoxic goiter. A decrease in the duration of cardiac hyperfunction and acceleration in the suppression of cardiac function in hypoxia were observed in rats with thyrotoxicosis though myocardial sensitivity to noradrenaline increased. After the discontinuation of hormone administration these changes rapidly disappeared but the general resistance of the body to hypoxia remained lowered and a response of the heart to acetylcholine sharply increased. In the thyrotoxic goiter a degree of myocardial hyperfunction in physical exercise was lowered in accordance with the gravity of a process, and the recovery of myocardial function after exercise slowed down. After therapy in the presence of a normal blood level of T4 a response of the heart to physical exercise returned to normal though the recovery of external respiration after exercise remained inhibited for a long time. The role of hypoxia in change of myocardial reactivity in thyrotoxicosis and the meaning of disorders of external respiration in preserving hypoxic manifestations in the post-thyrotoxic condition were discussed.

[Formation of the marginal "pro-oxidant" zone and its role in the enhancement of lipid peroxidation in the area of myocardial ischemia and infarction]. / Ob obrazovanii kraevoi "prooksidantnoi" zony i ee roli v usilenii perekisnogo okisleniia lipidov v oblasti ishemii i infarkta miokarda.

The formation of peripheral zone devoid of dehydrogenase activity but possessing vessels connected with the normal myocardium was demonstrated in the area of fresh myocardial infarction 2 h after coronary occlusion. A direct correlation between the changes of the zone area and the intensity of free radical lipid peroxidation in the area of fresh myocardial infarction was established.

[Characteristics of the "no-reflow" phenomenon in reperfusion of the myocardium depending upon the duration of ischemia]. / Osobennosti dinamiki fenomena "noreflou" pri reperfuzii miokarda v zavisimosti ot dlitel'nosti predshestvuiushchei ishemii.

The dynamics of changing dimensions of "no reflow" area following reperfusion after 30 min-1 h-long ischemia is characterized by three basic phases. The reperfusion following and hour-long ischemia altered considerably the character of phases of "no reflow" phenomenon. The data obtained suggest that the therapy of transitory ischemia must be directed not only to ischemia itself, but also to postischemia reperfusion-induced "no reflow" phenomenon.

[Changes in the size of the damage to the normal nonischemic myocardium adjacent to the risk area for infarct development in permanent and transient coronary occlusal ischemia]. / Izmenenie ploshchadi povrezhdeniia normal'nogo neishemizirovannogo miokarda, prilegaiushchego k "zone riska" razvitiia infarkta, pri postoiannoi i tranzitornoi koronarnookkliuzionnoi ishemii.

The results of morphometric analysis of the myocardial infarction area show that the involvement of normal myocardium, ajacent to the risk zone of infarction, into the damaging process is insignificant or absent both in continual and transitory ischemia.

[Effect of naloxone and thyroliberin on respiration in acute hypoxia]. / Vliianie naloksona i tiroliberina na dykhanie v usloviiakh ostroi gipoksii.

Experiments on 48 adult rats anesthetized with urethane were made to study the effects of naloxone and thyrotropin-releasing hormone on respiration after acute hemorrhage. The drugs were injected intravenously in doses 0.25-0.30 mg/kg. The changes found in the electromyogram of the diaphragm, blood pressure and ECG demonstrated naloxone and thyrotropin-releasing hormone to stimulate the respiratory center at different stages of respiratory disorders (dyspnea, apnea, gasping) induced by hemorrhage.