Increased resistance to heat shock of isolated hearts from rats adapted to moderate physical exercise

Hearts isolated from rats adapted to physical activity through moderate regular exercise (swimming) were more resistant to heat shock than hearts from unadapted controls. Thus, 15-min perfusion of control hearts with a solution heated to 42°C significantly depressed contraction amplitudes and caused a contracture amounting to 36% of the initial contraction amplitude, as well as increased release of creatine kinase into the perfusate. In the hearts from adapted rats, contraction amplitude was, on average, 2.3-fold greater and the contracture 3.2 times less marked than in the control animals; the test and control hearts did not differ significantly in the release of creatine kinase. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 256–258, March, 1995 Presented by S. S. Debov, Member of the Russian Academy of Medical Sciences     

Increased generation of nitric oxide in tissues of rats following their adaptation to short-term stress (An EPR study)

Adaptation of rats to short-term immobilization stress increases the ability of their isolated organs to generate nitric oxide (NO): its spontaneous release by the liver, gut, heart, and kidney tissues rises 2- to 4-fold and its carbachol-stimulated release by these tissues rises 4- to 5-fold. It is suggested that such adaptation leads to rapid NO generation in the adapted animal in response to exogenous or endogenous stimuli and thus increases the efficacy of defense reactions. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 3, pp. 242–244, March, 1994 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Development of aseptic inflammation during the adaptation of the organism to high altitude hypoxia

The dynamics of lipid peroxidation and of the aseptic inflammatory process is studied in rats adapted to high altitude hypoxia. A greater activity and shorter duration of the acute period of inflammation are found in these animals, while in the reparative period stimulation of the proliferative processes and slowed formation of the fibroblast capsule are noted. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 243–246, September, 1994 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Boosting the antitumor effect of doxorubicin by combined correction of hemostasis

The size of the primary tumor and number of metastases to the lungs in mice with Lewis pulmonary carcinoma treated with doxorubicin were, respectively, 3 and 2.2 times less than in the control. Injection of doxorubicin and heparin led to an 8-fold reduction of the tumor. The number of animals with detected metastases to the lungs and the mean number of metastases per animal were decreased. Supplementation of doxorubicin therapy with a complex of drugs correcting platelet aggregation and the antithrombogenic properties of the vascular wall resulted in a reduction of the number of metastases on the lung surface in comparison with the control and with the animals treated with doxorubicin alone. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2, pp. 204–206, February, 1995 Presented by A. F. Tsyb. Member of the Russian Academy of Medical Sciences     

The development of free radical processes in experimental bronchospasm. Effect of the bronchodilator preparation troventol

The development of bronchospasm is shown to be accompanied by lipid peroxidation (LPO) activation; 3-fold and 8-fold rises of malondialdehyde concentration are found in homogenate of lung from sensitized animals and from animals provoked with egg albumin antigen, respectively. The use of luminol-dependent chemiluminescence (CL) reveals that in sensitized rats the production of oxygen free radicals is increased by alveolar macrophages activated with phorbol myristate acetate. Troventol at 10⁻³ mg/ml inhibits the CL response of phagocytes both in intact and in sensitized rats and lowers the level of Fe²⁺-induced LPO in lung tissue but not in the liver of intact animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 619–621, June, 1994     

Changes in the coronary vessel tone resulting from immobilization stressA

Coronary perfusion pressure at increasing flow of Krebs-Henseleit buffer in the hearts of animals exposed to stress is decreased 23%, a decrease which is eliminated by administering the NO-synthase blocker N^G-monomethyl-L-arginine. Stimulated vasodilation of coronary vessels (administration of sodium nitroprusside and acetylcholine) decreases markedly in stressed animals; the concentrations of sodium nitroprusside and acetylcholine inducing a half-maximum coronary response increase. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 246–249, September, 1994 Presented by K. V. Sudakov, Member of the Russian Academy of Medical Sciences     

Opiatergic mechanisms of the cardiotropic effect of acute cooling

Changes in myocardial contractility after an acute cold exposure following intracerebroventricular administration of opiate receptor agonists were studied in rat hearts isolated after Langendorff. Cold exposures were carried out individually for each animal in chambers at −10°C for 4 h. Thirty min before being exposed to cold the animals were administered in a brain ventricle 10 μl of μ- or δ-opiate receptor agonists (DAGO or DADLE, respectively). Isolation and perfusion of the hearts were performed directly after the cold exposure was over. The mechanism of reduction of myocardial contractility and coronary flow induced by an acute cold exposure is believed to include stimulation of μ-opiate receptors as one of its main components, and the effect of intracerebral hypertension on hemodynamic parameters is partially mediated through activation of δ-opiate receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 582–584, December, 1994 Presented by R. S. Karpov, Member of the Russian Academy of Medical Sciences     

Regulation of therapeutic and toxic effects of cardiac glycosides by electromagnetic radiations,alternating magnetic and electric fields

A model of bioassay of the toxic and therapeutic effects of cardiac glycosides (strophanthin K) was used in experiments within situ isolated hearts of laboratory frogs. This model helped reveal effective parameters of modulating the effects of electromagnetic radiations and of alternating magnetic and electric fields. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 502–504, November, 1994 Presented by S. N. Golikov, Member of the Russian Academy of Medical Sciences     

Seasonal differences in the development of heightened resistance of the isolated heart during adaptation to physical exercise

Substantial seasonal differences are found in the development of the cardioprotective effect of adaptation to physical exercise: in winter such adaptation results in an increase of the resistance of the isolated heart to the contracture and arrhythmogenic effects of ischemia and reperfusion, while in summer the anticontracture effect is absent and the antiarrythmic effect is significantly lowered. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 9, pp. 299–301, September, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Adaptation to altitude hypoxia limits lipid peroxidation during inflammation and stress

Preadaptation of rats to altitude hypoxia results in reduced activation of lipid peroxidation during subsequent stress, inflammation, or both, as compared to hypoxiaunadapted animals, with the result that secondary changes in organs and tissues of adapted rats are much less pronounced and conditions are created for alleviating the acute inflammation and the stress reaction. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 590–593, June, 1995 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Effect of prenatal hypoxia on DNA synthesis in the tracheal epithelium and LPO-AOD system in the lungs of newborn rats

Newborn rats euthanized 24 h after birth were examined. The rats were born to females exposed to chronic hypobaric hypoxia on days 14–19 of gestation. The index of nuclei labeled with³H-thymidine in the tracheal epithelium of newborn rats exposed to prenatal hypoxia was 3 times lower than in the control. The LPO level was higher in posthypoxic animals than in intact rats. Prenatal hypoxia led to the suppression of antioxidant defense in the lungs of newborn rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 531–533, May, 1994     

On the involvement of endogenous μ- and δ-opiate receptor agonists in the antiarrhythmic effect of adaptation

Rats adapted to stress showed a decreased severity and incidence of cardiac arrhythmias induced by epinephrine, and these effects of adaptation were abolished by naloxone. It is suggested that stress adaptation mitigates arrhythmia by activating the endogenous opioid system and stimulating the μ-opiate receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp. 24–25, January, 1996 Presented by R. S. Karpov, Member of the Russian Academy of Medical Sciences     

Stimulation of proliferative activity of human natural killers (CD16+CD56+ cells) by recombinant interleukin-3in vitro

The proliferative activity of human natural killers (CD16⁺CD56⁺ cells) in the presence of 100 and 1000 IU/ml human recombinant interleukin-3 is investigatedin vitro. It is shown that recombinant interleukin-3 reliably enhances natural killer proliferation, causing a 9–15.2-fold increase of³H-thymidine uptake by CD16⁺CD56⁺ cells both in complete culture medium and in conditioned medium. The effect of the factor is 3.9–6.4 and 3.6–8.9-fold more potent than that of recombinant interleukin-2 and granulocyte-macrophage colony-stimulating factor, respectively, in the same doses. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 4, pp. 409–412, April, 1995 Presented by S. V. Prozorovskii, Member of the Russian Academy of Medical Sciences     

Protective effect of adaptation to hypoxia and its prolongation by pharmacological agents in rats prone to audiogenic epilepsy

Cytophotometric determination of RNA in various brain structures of hypoxia-adapted and unadapted epilepsy-prone rats at different times after an epileptic seizure shows much smaller decreases in RNA levels and their much more rapid return to normal in the adapted than in the unadapted rats. The adaptation to hypoxia produces a marked anticonvulsive effect, and this effect is enhanced and prolonged considerably by pharmacotherapy. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 120–123, February, 1994     

Metabolism of sialic acid-containing compounds in the gastric and intestinal mucosa in immobilization stress

The metabolism of sialoglycoproteins and ganglioside (free, oligo-, protein-, and lipid-bound sialic acids, and activity of sialidase) is studied in plasma and gastric and duodenal mucosa of rats subjected to immobilization stress for 8 days. Sustained alterations in these parameters are found in severely stressed animals. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 268–269, September, 1994 Presented by S. S. Debov, Member of the Russian Academy of Medical Sciences.     

Analysis of the effect of acupuncture on the regeneration of rat submaxillary salivary gland using the clusterization method

Cluster analysis of the effect of acupuncture on the regeneration of rat salivary gland reveals a diverse reaction: regeneration is enhanced in 19% of the animals, while in 32% it is suppressed, the intact contralateral part of the gland being atrophied. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 6, pp. 659–662, June, 1995 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Effect of various oxygen concentrations on the ATP content in isolated hepatocytes of rats adapted and nonadapted to hypoxia

It is shown that isolated hepatocytes are capable of perceiving slight changes in the envioronmental oxygen concentration. A complicated phase dependence exists between adenosine triphosphate and partial oxygen pressure, which differs in cells from animals with high and low resistance to hypoxia, the former showing a more stable and resistant energy-synthesizing function than the latter. After long-term adaptation to periodic hypoxia, the resistance of the energy-synthesizing function rises in hepatocytes from high-resistant animals, and falls in low-resistant animals suggesting a fundamentally different organization of the emergency compensatory mechanisms of the energy-synthesizing function in hepatocytes of animals of these two types. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 576–581, December, 1994     

Morphological study of somatic muscles in alimentary-toxic paroxysmal myoglobinuria

The development of acute focal metabolic lesions of somatic muscles is shown in alimentary-toxic paroxysmal myoglobinuria. Two principal universal reactions of striated muscles are traced in the genesis of this pathological process, namely, contracture damage and intracellular myocytolysis. The functional asynchronism and structural-metabolic heterogeneity of muscle fibers are reflected in the stagewise and typical heterogeneity of the morphological picture, which preserves the entire spectrum of stereotypical pathological reactions regardless of the severity of the illness. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 228–233, February, 1996 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

The uptake of 3-deoxy-3-iodine-glucose by normal and tumor cellsin vitro

It is found that 3-deoxy-3-iodine-glucose (3D-I-glucose) enters both erythrocytes and tumor cells at a rate close to that of glucose entry. For tumor cells the total uptake of the preparation was 6-fold higher than for erythrocytes (1500 and 250 μM/mln. cells, respectively). Phosphorylated products of 3D-I-glucose were not detected; however, the total amount of preparation in the probes dropped during incubation, indicating that it is metabolized by the cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 6, pp. 654–655, June, 1994     

Mice selected for low brain weight show heightened sensitivity to the convulsive action of pentylenetetrazole

Convulsive activity of pentylenetetrazole (25–120 mg/kg) measured in mice selected for large or small brain weight was evaluated, and mice with a smaller brain weight proved to be more susceptible to the damaging action of this compound than those with a larger weight. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 460–462, May, 1995 Presented by V. S. Rusinov, Member of the Russian Academy of Medical Sciences