Effect of L-arginine on myogenic reactions of vascular smooth muscle cells in hypercholesterolemia

In hypercholesterolemia, the reduced vascular response observed during stretching of the vessel wall is probably caused by disorders of endothelial functional activity. L-arginine stimulates synthetic activity of the endothelium, making it possible to use of this amino acid for correction of these impairments. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2, pp. 118–120, February, 1995 Presented by B. I. Tkachenko, Member of the Russian Academy of Medical Sciences     

Functional activity of blood mononuclear cells during regeneration of bone tissue

It is established that, during elongation of a segment of the extremity, normal regeneration of the bone tissue is attended by a slight decrease in monocyte adherence during the postoperative period and by an increase of the functional activity of lymphocytes during subsequent activation of osteogenesis. Suppression of the lymphoid apparatus is observed in the case of disturbed osteogenesis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 1117, N ^o 1, pp. 104–105, January, 1994     

Responses of the arterial and venous vessels of the skeletal muscle to norepinephrine following damage to their endothelium

The functional activity of vascular endothelium in a muscle preparation from the feline gastrocnemius is impaired with ethanol, which results in an increase of an adrenergic responsiveness of the arterial compartment of the vascular bed. The exchange function of the microvessels changes little. Veins exhibit nonuniform changes in their responsiveness after exposure of their endotheliocytes to ethanol. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 9, pp. 315–318, September, 1994     

Ultrastructural analysis and autoradiography of the gastric mucosa in chronic gastroduodenal ulcer

The mucosa of the fundal and pyloric portions of the stomach in chronic gastroduodenal ulcer is shown to exhibit structural and functional heterogeneity. Regularities of the regenerative-plastic reactions in the epithelium are revealed from the indexes of³H-uridine and³H-thymidine incorporation. Inflammatory-sclerotic changes of the gastric mucosa showed different proliferative and metabolic activity of epitheliocytes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 198–202, August, 1994 Presented by L. D. Sidorova, Member of the Russian Academy of Medical Sciences     

Using the method of evoked short-latency brainstem potentials in asthmatic patients with hyperventilation syndrome

The method of evoked short-latency brainstem potentials in a group of patients with bronchial asthma attended by hyperventilation syndrome demonstrates disturbances of the functional activity of the brainstem structures, this attesting to dysfunction of the mesencephalic and cerebropontine zones. No changes are observed in a group of patients without hyperventilation syndrome. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 138–139, February, 1994 Presented by A. D. Ado, Member of the Russian Academy of Medical Sciences     

Effects of fibroblast-keratinocyte interactions on the secretion of interleukin-8

Using two models for preparing skin equivalent, the effects of interactions between various types of fibroblasts and keratinocytes on their secretory activity in the production of interleukin-8 are studied. The secretion of an antiinflammatory cytokine is found to depend on the type and function of fibroblasts, the level of their proliferative activity, and the extent of formation of the dermal layer. Keratinocytes are capable of recognizing fibroblast function and stimulate or inhibit the secretion of interleukin-8 depending on the functional status. A new concept of hyperkeratosis and parakeratosis in psoriasis is proposed, which is based on a defect in the autoregulation of mediators, specifically, interleukin-8. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 181–184, February, 1996 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Ca2+ transport of the skeletal muscle sarcoplasmic reticulum during readaptation of rats after a 40-day load relief on the hind paws

The rate of Ca²⁺ accumulation in the sarcoplasmic reticulum of the skeletal muscle (m. gastrocnemius lateralis, m. vastus medialis, andm. soleus) is studied in rats under conditions of functional off-loading of the hind paws (suspending animals by the tail). The rate of Ca²⁺ transport in the sarcoplasmic reticulum is shown to be stepped up in all these muscles. In the sarcoplasmic reticulum ofm. gastrocnemius lateralis andm. vastus medialis the Ca²⁺ transport rate reliably drops, which does not occur inm. soleus. During a 2-week period of readaptation of animals suspended for 40 days, the Ca²⁺-transporting function of them. soleus sarcoplasmic reticulum gradually recovers to reach the control values, whereas the time course of recovery of Ca²⁺-pump activity in the sarcoplasmic reticulum ofm. gastrocnemius lateralis andm. vastus medialis has a phasic pattern. Translated fromByulleten' Eksperimental'noi Biologii i Meditsity, Vol. 118, N ^o 12, pp. 591–595, December, 1994 Presented by A. I. Grigor'ev, Member of the Russian Academy of Medical Sciences     

Ca2+ transport in the myocardial sarcoplasmic reticulum of rats during antiorthostatic off-loading and during readaptation

The rate of Ca²⁺ accumulation in the myocardial sarcoplasmic reticulum is studied in experiments on rats under conditions of hind paw functional off-loading by suspending animals by the tail for 1 to 40 days, as well as during a 2-week period of readaptation after a 40-day load relief. The rate of Ca²⁺ transport in the myocardial sarcoplasmic reticulum reliably drops (by 33%) after 40 days of suspension. At earlier stages of off-loading Ca-pump activity in the sarcoplasmic reticulum does not change reliably. After resumption of the loads in animals suspended for 40 days, the transporting function of the myocardial sarcoplasmic reticulum rapidly reverts to the control level, which is indicative of a reversible pattern of load relief-induced changes in the rate of Ca²⁺ transport. Translated fromByulleten' Eksperimental'noi Biologii i Meditsity, Vol. 118, N ^o 12, pp. 596–599, December, 1994 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Effect of human defensins on the cytoplasmic Ca2+ content in platelets

The effect of the total fraction of human defensins (HNP-1, HNP-2, and HNP-3) on the cytoplasmic Ca²⁺ content ([Ca²⁺]_i) in the platelets of healthy donors was studied. At concentrations of 0.1–40 μg/ml and an incubation time of 10 min defensins have no effect on [Ca²⁺]_i in platelets labeled with Fura-2AM. However, at higher concentrations (100 μg/ml) they increased platelet [Ca²⁺]_i. In addition, defensins (40 μg/ml) inhibited the Ca²⁺ increase in platelets induced by thrombin, adenosine diphosphate, and the lipopolysaccharide ofS. typhimurium endotoxin. The most pronounced inhibitory effect was observed in a suspension of thrombin-stimulated platelets. It is shown that the effect of human defensins on the functional activity of platelets is due to the alterations in the intracellular Ca²⁺. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 600–603, December, 1994     

Specific features in the secretory activity of enterochromaffin cells of the duodenal mucosa of red-cheeked souslik under different physiological conditions

The ratio of the synthetic and secretory phases of the activity of duodenal enterochromaffin cells of the hibernating red-cheeked souslik under hypo- and normothermia is compatible with the functional significance of serotonin, one of their secretory products. The synthesis and accumulation of the secretion predominate during normothermia in summer and winter, whereas during deep torpor serotonin is mainly released from the cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3 pp. 337–340, March, 1996 Presented by V. P. Kaznacheev, Member of the Russian Academy of Medical Sciences     

Immunological responses during the organism's adaptation to a dosed thermal factor

Overheating of mice over the course of 10 and 20 days suppresses the proliferative activity of splenic cells in response to stimulation with phytohemagglutinin, concanavalin A, lipopolysaccharide, pokeweed mitogen, and alloantigens. The number of antibody-producing cells in the spleen drops on day 5 of overheating and is still low on days 10–20. Forty days after the start of overheating the functional activity of lymphocytes is restored. Overheating of animals does not change the colony-forming activity of hemopoietic stem cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 502–504, May, 1994 Presented by N. A. Vasil'ev, Member of the Russian Academy of Medical Sciences     

Effect of perfluorodecalin on picrotoxin toxicity and some detoxication systems

Preliminary administration (at least 7 days before the experiment) of perfluorodecalin boosts resistance to the toxic action of picrotoxin in rodents. The antidotal activity of diazepam rises under these conditions. Perfluorodecalin induces the activation of monooxygenase, conjugation, and antioxidant detoxication systems; the protein content increases in the blood serum and carboxylesterase activity is enchanged. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2. pp. 176–178, February, 1995     

Evalution of changes in secretion of active oxygen forms by polymorphonuclear lymphocytes

The increased NBT activity of leukocytes in immunized rabbits is found to be dependent on the antigen concentration and is probably related to the direct effect of antigen on the cells. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 163–165, February, 1994 Presented by Yu. A. Vladimirov, Member of the Russian Academy of Medical Sciences     

The effect of delta-sleep-inducing peptide on the Ca-transporting system of the sarcoplasmic reticulum and activity of the myocardial antioxidant enzymes

It is demonstrated that immobilization stress against the background of lowered catalase activity impairs the function of the sarcoplasmic reticulum Ca pump, particularly at high Ca²⁺ levels. the membranes of intracellular Ca²⁺ depots are destroyed much more rapidly than in the control, which results in Ca²⁺ release. Administration of delta sleep-inducing peptide to control animals results in a 30% increase in catalase activity for an unchanged level of superoxide dismusase and markedly improves the function of the Ca-transporting system at elevated levels of free Ca²⁺. A long-term stress after administration of the peptide not only causes no damage to the Ca-transporting system but actually increases its efficiency (compared with the control) at a high catalase level. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 248–251, March, 1996 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Role of the specific determinant of group A streptococcus polysaccharide in inhibition of T-suppressor activity

Group A streptococcus polysaccharide is found to inhibit the activity of ConA-stimulated T suppressors. A-variant streptococcus polysaccharide, representing an L-rhamnose homopolymer which is identical to the rhamnose carcass of group A streptococcus polysaccharide, does not possess such an effect. The effect of group A streptococcus polysaccharide on the activity of T suppressors is considered to be associated with its determinant including N-acetylglucosamine as an obligatory component. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2, pp. 201–203, February, 1995 Presented by S. V. Prozorovskii, Member of the Russian Academy of Medical Sciences     

Na+/H+ countertransport and calcium exchange in peripheral blood cells of healthy subjects and patients with chronic heart failure

A comparative study is performed of Na⁺/H⁺ exchange and Ca²⁻ mobilization in erythrocytes and platelets of patients with stage I–II chronic heart failure caused by dilative cardiomyopathy and ischemic heart disease. A significant rise in the Na⁺/H⁺ exchange rate is found in the cells of chronic heart failure patients, which correlates with an elevated erythrocyte and platelet concentration of Ca²⁺ and an increased “calcium” response of platelets to inductors. The findings testify to a certain functional relationship between various cation-transporting cellular systems whose change in properties upon chronic heart failure can play an important pathogenic role. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 12, pp. 572–575, December, 1994     

Vestibuloprotective activity of seal serum proteins

Cat and rat experiments show that the protein fraction isolated from blood serum of the Greenland seal has a protective activity against motion sickness. This activity is comparable to that of the classical vestibuloprotector scopolamine and is greater than that of diprazine. Radioligand assay of the receptor binding showed that the serum protein fraction has the highest affinity for α₂-adrenoceptors, μ-opioid, and benzodiazepine receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol 117, N ^o 4, pp. 444–445, April, 1994     

Effects of hydrocortisone,retabolil, and their combination on the phagocytic activity of rat blood neutrophils

Effects of retabolil on the phagocytic index, phagocytic number, and the nitro blue tetrazolium reduction test with rat blood neutrophils were studied. The drug was found to reduce these parameters. Pretreatment with retabolil arrested or attenuated the depression of neutrophil phagocytic activity caused by hydrocortisone. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 2, pp. 179–180, February, 1995     

A study of the mechanism of action of befol on Ca2+ metabolism in cardiomyocytes using a FURA-2 fluorescent probe

The dynamics of the Ca-response of cardiomyocytes is studied and the efficiency of befol, verapamil, and amiodarone is compared using various experimental models of stimulation of [Ca²⁺]_i. Befol (1–5 μM) is shown to inhibit the caffeine-and strophanthin G-induced rise of [Ca²⁺]_i. Unlike verapamil and amiodarone, befol exhibits no Ca-blocking activity in modeled K-depolarization. It is concluded that the cardiotropic effect of befol is mediated through its primary action on Na⁺/Ca²⁺ exchange in cardiomyocytes, while the cardioplegic effect of verapamil and amiodarone is due to their ability to block the slow Ca²⁺ inward current. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 288–291, March, 1996     

Functional activity of human leukocytes exposed to a hypotonic medium

This study, in which zymosan-stimulated luminol-dependent chemiluminescence of leukocytes was used to examine the osmotic resistance and functional activity of peripheral blood leukocytes from 23 patients with purulent septic lesions and 11 healthy donors before and after exposure of these cells to a hypotonic medium (0.45% NaCl), showed that this medium stimulated their spontaneous chemiluminescence while reducting their reserve capacities. The effects of the hypotonic medium on cells from the patients were more strongly marked. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 93–94, July, 1994 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences