[Features of the metabolism of nitric oxide in normal state and inflammation].

Brief analysis of the metabolism of nitric oxide in living cells in normal state and pathology and also the analysis of the causes, that hampered the progress of these studies, were carried out. It was established that most of physiological fluids, including blood, normally contain nitrite and non-thiolate nitroso compounds in concentration less than 100 nM. Literature data from different researchers on the normal range of nitrite concentration in plasma of healthy people from several hundreds of nM to several microM is probably the result of low selectivity of the methods used. But nitrite and non-thiolate nitroso compounds concentration in blood is dramatically increased in case of inflammatory diseases. It is proposed that the main mechanism for the production of these substances in blood is the nitrosyl iron complexes transformation by active oxygen species but not the activation of NO production as it was-considered previously.

Mechanism of therapeutic effect of low-intensity infrared laser radiation.

The effect of infrared low-intensity laser irradiation on functional activity of blood polymorphonuclear leukocytes was studied in vitro. A dose-dependent priming of polymorphonuclear leukocytes induced by infrared low-intensity laser irradiation was demonstrated. Similar effects were also observed in the presence of the photosensitizer photosense.

Priming of phagocytes by cytokines and water-soluble products of lipid peroxidation.

It is well known that during certain pathological processes phagocytes acquire the ability to generate activated oxygen species during phagocytosis. The priming of phagocytes by cytokines and water-soluble products of lipid peroxidation (LPO) is described. Preincubation of human polymorphonuclear leukocytes (PMNL) with the water-soluble products of LPO or oxidised liposomes for 15-20 min at 37 degrees C enhanced their functional activity when they were stimulated by opsonised zymosan or latex particles. There was a 2-3-fold increase in luminol-dependent chemiluminescence response of cells stimulated in this way, and an increase in Fc-receptor expression on the PMNL surface. An endogenous cytokine alone did not activate the phagocytes for an oxidative burst response, but preincubation of murine peritoneal macrophages (MP) and human PMNL with cytokines (molecular mass 20-30 kDa) for 3-48 h at 37 degrees C enhanced the cell chemiluminescence response to opsonised zymosan by a factor of 5-9 for MP and a factor of 2-3 for PMNL. Treatment of phagocytes with the cytokine complex also increased other effector functions of the phagocytes such as tumouricidal activity, phagocytosis, secretion of interleukin-1, and antiparasitic activity. The protein synthesis inhibitor cycloheximide abolished cytokine-induced priming of MP (but not of PMNL). The mechanisms of short-term and prolonged priming of the two types of phagocytes (MP and PMNL) are discussed.

[Changes in the superoxide dismutase activity during stimulation of polymorphonuclear leukocytes of peripheral blood]. / Izmenenie aktivnosti superoksiddismutazy v protsesse stimuliatsii polimorfnoiadernykh leikotsitov perifericheskoi krovi.

The functional activity of the peripheral blood polymorphonuclear leukocytes (PML) was investigated by using the method of latex-stimulated luminol-dependent chemiluminescence (CL). The CL-intensity of PML taken from patients with acute myocardial infarction (MI) was found to be 20 times higher than that of normal individuals (NI). The change in activity of endogenous antioxidative enzyme systems may account for alteration of PML CL-parameters. It was established that the initial superoxide dismutase (SOD) activity of unstimulated PML from patients with MI exceeds that of NI, and that rapid increase in intercellular SOD activity (within 30 sec.) occurs in the process of PML stimulation. It was suggested that the change of SOD activity during PML stimulation was the result in the enzyme partial proteolysis in the cells. The positive correlation between initial level of SOD activity and CL-intensity of PML was observed. The investigation of the above parameters in MI dynamic showed a gradual normalization of PML CL-response and insignificant decrease in intracellular SOD activity in case of a favourable cause of the disease. Increased SOD activity in PMLs may be one of the factors contributing to a decrease in PML functional activity in the disease dynamic.

[Characteristics of immune complexes in myocardial infarct]. / Osobennosti immunokompleksnogo protsessa pri infarkte miokarda.

Nonspecific circulating immune complexes (CIC), different in size and stability, are detectable in the blood sera of patients with myocardial infarction; changed concentration of these complexes appears to be a reflection of the defense response of the body, aimed at homeostasis maintenance. No relationship between cardiac glycosides and CIC levels was revealed in patients with myocardial infarction. A reduction of the level of 'large' CICs by days 21-30 of the condition was observed in the patients treated with anticoagulants from the first day of the disease. A low CIC level in the acute period of the disease is a prognostically unfavorable sign in respect of the outcome of the condition.

[The functional heterogeneity of circulating polymorphonuclear leukocytes in acute myocardial infarct]. / Funktsional'naia geterogennost' tsirkuliruiushchikh polimorfnoiadernykh leikotsitov pri ostrom infarkte miokarda.

Cytofluorometric analysis, using immune complexes, consisting of human IgG and fluorescein isothiocianate (FITC)-labelled monospecific rabbit antibodies to human IgG, as fluorescent markers for polymorphonuclear leukocytes (PML), and microscopic analysis of modified NST-test probes with NADH2 or NADFH2 were employed to investigate PML functional heterogeneity of healthy individuals and patients with acute myocardial infarction. It was shown, that circular PML make up heterogeneous cell population in the following parameters: Fc gamma-receptors expression, oxidative derivates generation and cell oxidases activity and the degree of heterogeneity may change during nonspecific inflammatory process, which accompanies acute myocardial infarction.

[Dynamics of changes in the functional activity of blood polymorphonuclear leukocytes in reversible myocardial ischemia in dogs]. / Dinamika izmeneniia funktsional'noi aktivnosti polimorfnoiadernykh leikotsitov krovi pri obratimoi ishemii miokarda u sobak.

Changes in peripheral blood polymorphonuclear leukocytes (PNL) functional activity in dogs during pre- and post-ischemic periods was investigated using the model of dogs venous circulation reversible disturbances in the chronic experiment and luminol-dependent chemiluminescence method. It was demonstrated that single transitory myocardial ischemia (MI) (5 min.) causes positive increase in PNLs functional activity by the 12th-14th hour of post-ischemic period. Repeated short-term MI (5 min.) was accompanied by the increase in phagocytes activity occurring 6-8 hours following the beginning of post-ischemic period, i.e. two times faster than in the case of primary ischemia. The results obtained allow the conclusion that the accumulative effect of multiple MI and the increase in PNLs functional activity as one of the reasons of cardiomyocytes injury in ischemic region cause pronounced inflammatory and necrotic myocardial changes.