[Physiological properties of the blood vessel smooth muscles in experimental atherosclerosis]. / Fiziologicheskie svoistva gladkoi muskulatury sosudov pri eskperimental'nom ateroskleroze.

The contraction of smooth muscle cells in response to the effect of catecholamines and potassium chloride was studied in experiments on isolated ring segments of the rabbit aorta under normal conditions and in experimental cholesterol atherosclerosis at its early developmental stages. It was found that at the early stages of atherosclerosis development the character of the contractile reactions was marked by changes which may be considered from the standpoint of disorder in the ion mechanisms of the interrelationships of sodium and calcium both on the membrane and within the smooth muscle cell, and from the standpoint of increased reactivity of chemically sensitive calcium channels of the membrane. The cause of these changes may be the accumulation of cholesterol, lipoproteins and acid mucopolysaccharides in the vascular wall at the early stages of atherosclerosis development.

[Pathogenetic basis of the diagnosis and treatment of lymphedema of the lower extremities]. / Patogeneticheskie osnovy diagnostiki i lecheniia limfedemy nizhnikh konechnostei.

A combined clinico-morpho-physiologic investigation was conducted in 98 patients with primary and secondary lymphatic edema. All patients underwent lymphography by means of electron and light microscopy; biopsy specimens obtained from a lymphatic vessel at lymphography were investigated histologically, and contractility records were made. Pronounced disorders were demonstrated in the lymphatic vessels and their myocytes. New rational schedules of pathogenetic treatment for lymphedema of the lower limbs are outlined on the basis of the reported findings.

[Self-regulation of the pump function of the lymphangion]. / Samoreguliatsiia nasosnoi funktsii limfangiona.

The pump function was studied in single isolated lymphangions of the bovine mesenteric vessels 2.5-3.5 mm in diameter. The lymphangion was found to be able to self-regulate the pump function. The terminal diastolic pressure 0.5-1.0 kPa was found to be optimal for the pump function. The ratio of the lymphangion power to its weight is 0.2 Wt/N at the pressure 1 kPa. i.e. the lymphangion is near to the heart of warm-blooded animals by this parameter. Mainly the myocytes of circular layer contribute to the lymphangion pump function, the myocytes carrying out the function of stretch receptors enabling the lymphangion to alter its efficacy in accordance with the level of lymph production.

[Electrical and contractile activity of the lymphangions of the mesenteric lymphatic vessels]. / Elektricheskaia i sokratitel'naia aktivnost' limfangionov bryzheechnykh limfaticheskikh sosudov.

The electrical activity of smooth muscle of isolated lymphangiomas revealed spontaneous APs about 3.8 +/- 1.3 mV for 200-250 ms preceding the contractions. In Ca-free solution the APs and the contractions disappeared. The blockade of calcium channels suppressed electrical activity of smooth muscle cells. The increase of amplitude and time of the APs increased the amplitude and time of the contractions. The data suggest that spontaneous APs play a part in activation and coordination of the phasic contractions, and show that automaticity of lymphangiomas is revealed in smooth muscle cells of the circular layers of the valves, and that tonic and phasic contractions have a special type of membrane activating mechanisms.

[Adrenergic and cholinergic mechanisms of the contractile reactions of major blood vessels]. / Adrenergicheskie i kholinergicheskie mekhanizmy sokratitel'nykh reaktsii magistral'nykh mozgovykh sosudov.

Epinephrine, norepinephrine, and isoproterenol induced circular contraction of isolated segments of canine intracerebral internal carotid artery. The alpha--and beta-antagonists inhibited the effects of catecholamines. Acetylcholine showed dual effects involving both dilation (5.10(-12)--5.10(-9) g/ml) and contraction 5.10(-8) g/ml and higher). Atropine inhibited both effects. The K+ depolarization abolished the contractile effects of norepinephrine and acetylcholine. The blockade of calcium permeability by Mn++ abolished the contractile effects of sympathetic and parasympathetic mediators.

[Effect of potassium ions on the contractile activity of renal artery smooth muscle]. / Vliianie ionov kaliia na sokratitel'nuiu aktivnost' gladkikh myshts pochechnykh arterii.

Study of isolated segments of renal arteries in rabbits showed that decrease of potassium ion concentration in the bathing fluid was followed by increase in tension, while its increase from 5 meq/l to 10 meq/l was accompanied by gradual relaxation of vessel muscles and increase of their sensitivity to noradrenalin (NA). This relationship was lacking in segments activated with NA. The ability of NA and angiotensin to activate renal arterial muscles by electromechanic and pharmacomechanic coupling mechanismes was proved experimentally. The paper discussed the role of the cell membrane sodium potassium pump in vascular muscles.

[Inhibition of spontaneous lymph vessel contraction evoked by transmural stimulation]. / Tormozhenie spontannykh sokrashchenii limfaticheskikh sosudov, vyzyvaemoe transmural'noi stimuliatsiei

In isolated sections of mesenteric lymphatic vessels, the constrictory responses to transmural electrical stimulation were studied. Inhibition of the spontaneous rhythm occurring primarily at low frequencies was revealed as well as the inhibition following the excitatory effect of high--frequency stimulation. Analysis of the transmural inhibition showed the latter to occur as the result of activation of adrenergic nervous plexus and to be fulfilled by the beta--adrenoreceptors.

[Mechanism of action of intravascular pressure on the electrical and contractile activity of lymphangions]. / Mekhanizm deistviia vnutrisosudistogo davleniia na élektricheskuiu i sokratitel'nuiu aktivnost' limbangionov.

Increased intravessel pressure resulted in depolarization of the smooth muscle cell membrane in lymphatic vessels, elongation of APs, augmentation of oscillatory potentials plateau and in increased steadiness of the smooth muscle cells in Ca--free solution, D-600 and Mn2+. The membrane of smooth muscle cells of lymphatic vessels seems to have Na-Ca channels with mechanical sensitivity.

[Ionic mechanisms of the electrical activity of the smooth-muscle cells of the lymphatic vessels]. / Ionnye mekhanizmy élektricheskoi aktivnosti gladkomyschechnykh kletok limfaticheskikh sosudov.

APs of smooth muscles of isolated lymphatic vessels were recorded by means of the single sucrose-gap method. Plateau APs with sharp spikes on the plateau were recorded in Krebs' solution. Low-sodium solutions led to discontinuation of the plateau phase whereas calcium-free solution eliminated the sharp spikes. Increase of the intravascular pressure during the action of D-600 blocking agent activated the electrical activity which suggests that smooth muscle cells have channels of mechanical sensitivity. Intracellular Ca2+ seems to participate in the contractile mechanism.

[Effect of pH, pCO2, and pO2 on renal artery contractility and reactivity]. / Vliianie pH, pCO2, i pO2 na sokratimost' i reaktivnost' pochechnykh arterii.

In isolated segments of the dog and cat renal arteries alkalization of the bathing solution at pH from 6.5 to 8.0 increased the amplitude of contraction and the sensitiveness to noradrenaline. A sharp rise of O2 content induced some increase in reactivity of muscle cells and caused spontaneous rhythmic activity. The results suggest a direct effect of pH and pO2 on the functional characteristics of renal arterial muscles. The effect seems to occur due to reversible changes in intracellular pH.

[Effect of stretch on the contractile response of isolated portal vein smooth muscle]. / Vliianie rastiazheniia na sokratitel'nye otvety gladkoi muskulatury izolirovannoi vorotnoi veny

The character of spontaneous activity of the isolated preparation was shown to be affected only by the first stretching stimulus which was due to release of the intracellular Ca. Active contractile responses to stretching at the peak of the contracture due to perfusion of the preparations with the Krebs sodiumless solution, are directly correlated with the speed of the stretching. Stretching of the preparations in calciumless solution elicited no active response.

[Active and passive mechanical properties of the wall of the lymphangion]. / Aktivnye i passivnye mekhanicheskie svoistva stenki limfangiona.

The modules of elasticity of circular stripes of lymphangion wall were 3.5.10(4) N.m-2, and those of longitudinal stripes were 1.5.10(5) N.m-2. The module of elasticity of intact lymphangions ranged from 1.2.10(4) to 5.2.10(4) N.m-2. The volume-pressure relationship in intact lympangions were similar to length-force relationship in circular stripes. Spontaneous contractions were only evoked by distention of circular stripes. These findings suggest that smooth muscle of circular layer of lymphangion's wall seems to play a basic role in pumping function of lymphangions.

[Effect of the rest interval on the contractile activity of the myocardium]. / Vliianie intervala pokoia na sokratitel'nuiu aktivnost' miokarda.

Isolated strips of the heart auricles and ventricles of frogs at high stimulation frequencies revealed rest potentiation which depended both on the stimulation rhythm and on the duration of rest interval. Amphibians as well as warm-blooded animals and fish seem to display a possibility of Ca++ entering a cell during the period of rest via non-electrogenic calcium canals, but in amphibians this mechanism of the myocardium activation is compansatory, rather.

[The contractile and electrical activity of the smooth muscles of the major lymph vessels]. / Sokratitel'naia i elektricheskaia aktivnost' gladkikh myshts magistral'nykh limfaticheskikh sosudov

In rats, catecholamines were found to increase the rate of the muscles spontaneous rhythmic contractions while the alpha- and beta-blocking agents suppressed them. The spontaneous contractions were blocked in the uncalunm medium. Rhythmic electrical stimulation evoked contracture-like responses the uncalunm of which depended on the strength, frequency, and duration of the stimulation. In spontaneoulsy active preparations, single electrical stimuli evoked contractions according to the "all or nothing" rule. The membrane potential magnitude varied within the limits of 25-37 mV, and action potentials were related to the contractions. The data obtained suggest that the functional unit of conduction of spontaneous or evoked excitation waves is represented by a group of smooth muscle cells within a single lymphangion.

[Analysis of chrono-inotropy of the myocardium in poikilothermic animals]. / K analizu khrono-inotropii miokarda poikilotermykh zhivotnykh.

Chrono-ionotropic interrelationships were studied in isolated strips of the myocardium of poikilothermous animals (frogs and fishes) in conditions of either stationary or transitional regimens of stimulation. In the stationary regimen, the rhythm-strength relation is simple and corresponds to a parabolic curve. While changing the lesser frequency of stimulation for greater one, both the positive and negative transitional abbreviating stirs were observed, in contrast to literature references. The phenomena of positive and negative transitional stairs were concluded to be unrelated to species while being a general biological form of the myocardium response to change of the stimulation rhythm.

[Activation mechanisms for contractions of the smooth musculature of the cerebral vessels]. / Mekhanizmy aktivatsii sokrashenii gladkoi muskulatury mozgovykh sosudov

Pial arteries and veins were found to differ by their contractile features. Pial arteries are highly sensitive to noradrenaline, adrenaline, histamine, serotonin, rapid stretching, and potassium ions. The effects of the mediators, potassium ions, and rapid stretching could be blocked by manganese ions. Pial veins are insensitive to the mediators effects, potassium ions, or rapid stretching, although they are highly sensitive to transmural electric stimulation. Manganese ions have no effect on the veins' responses to electric stimulation. A spontaneous activity of the smooth muscle cells of the a. carotis' intracranial portion was revealed in man. The activation mechanisms for the cerebral arteries smooth muscle contractions are suggested to depend on the calcium extracellular ions. The activation mechanism for the veins' smooth muscle contractions depends on the intracellular store of calcium ions.

[Activation mechanisms of the contractile cells of cerebral arteries and veins]. / Issledovanie mekhanizmov aktivatsii sokratitel'nykh kletok mozgovykh arterii i ven.

In isolated strips of internal carotid artery and middle cerebral artery in humans, spontaneous electric and contractile activities were revealed. Low (35 degrees C) and high (40--41 degrees C) temperatures inhibited the development of spontaneous contractions. Under depolarization of the cells' membranes by potassium ions, no development of spontaneous electric or contractile waves occurred, while contractions of the tonic type were observed in arterial preparations. No spontaneous contractions were found in the cerebral veins.

[Action potentials of the heart atria and ventricles of Rana temporaria frogs and Cyprinus carpio carp]. / Osobennosti potentsialov deistviia predserdii i zheludochkov serdtsa liagushki Rana temporaria i karpa Cyprinus carpio

Using microelectrode technique, studies have been made on electrophysiological indices (amplitude of AP, amplitude of the plateau, latent period of AP, duration of maximal depolarization, duration of repolarization at different levels) of cells of isolated atrium and ventricles of the carp during both the spontaneous activity and electrical stimulation. The obtained amplitude-temporal parameters were compared to those of the heart in the frog R. temporaria. It was found that the amplitude of AP, the amplitude of the plateau and the duration of the latent period of AP in both the atrium and ventricles of the carp significantly (p less than 0.01) differ from the corresponding indices of the frog. On the contrary, the duration of maximal depolarization and repolarization in cells from homologous parts of the heart is very close in the species investigated.