[The functional state of thymus cells under prolonged combined action of phenobarbital and E. coli lipopolysaccharide]. / Funktsional'noe sostoianie kletok timusa v usloviiakh dlitel'nogo kompleksnogo deistviia fenobarbitala i lipopolisakharida E coli.

The effect of separate and combined 10-day treatment with phenobarbital (PB) in a single daily dose of 35 mg/kg and E. coli lipopolysaccharide (LPS) in a dose of 25 microg/kg was studied in white rats. The results were evaluated by the rate of DNA synthesis in the culture of T mitogen stimulated thymocytes, the activity of glucose-6-phosphate dehydrogenase (G-6-PDG) in the thymus, and the activity of acetylcholine esterase (ACE) and the content of catecholamines (CA) in the nerve fibers of this organ. It was established that the 10-day treatment with PB inhibits the proliferative activity in concanavalin A stimulated lymphocytes of rat thymus, decreases the ACE activity, and increases the CA content in the nerve fibers. The repeated injections of E. coli LPS on the background of PB led to more pronounced negative changes in the functional activity of lymphoid cells in the thymus, manifested by a decrease in the G-6-PDG activity and the rate of DNA synthesis in the thymus and by an increase in the level of biogenic amines in the nervous fibers of this organ.

[Effect of low-intensity electromagnetic fields of industrial frequency on the ultrastructure and proliferative activity of rat's thymus cells]. / Vliianie nizkointensivnykh élektromagnitnykh polei promyshlennoi chastoty na ul'trastrukturu i proliferativnuiu aktivnost' kletok timusa krys.

Effects of two types of low-intensity electromagnetic fields (EMF) of industrial frequency (50 Hz) on the fine structure and proliferative activity of thymic cells in white rats were studied. It was found that a weak EMF with a prevailing electrical component (380-480 V/m, 120-140 nT1) did not affect the DNA synthesis intensity. An EMF with a stronger magnetic induction (10-15 V/m, 800-1500 nT1) diminished the glucose-6-phosphate dehydrogenase activity and proliferative processes in cultured stimulated lymphocytes. Electron microscopic investigation of the thymus after both types of exposure revealed an accumulation of lymphocytes with pyknotic nuclei and electron-dense cytoplasm, as well as hypoplasia of the vascular endothelium. At the same time, EMF with a prevailing magnetic component produced a more marked negative effect on the ultrastructure of thymic cells, which indicated a lowered secretory activity of epitheliocytes.

[Neuroimmune relations in the rat thymus caused by recombinant interleukin-1beta administration]. / Izuchenie neroimmunnykh otnoshenii v timuse krys pri deistvii rekombinantnogo interleikina-1beta.

Interrelations among changes in 11-oxycorticosteroids (11-OSC) in blood plasma, catecholamines (CA), and acetylcholinesterase (AChE) activity in nerve fibres of the thymus, as well as qualitative content and proliferative capacity of thymic and blood cells under the effect of the rat recombinant interleukin-1 beta (IL-1beta) normally and under conditions of hypothalamic-pituitary-adrenocortical depression, were studied. The changes were the most obvious within 15 and 120 min following the IL-2 beta administration: elevation of the 11-OSC, increase in the CA content, and decrease in the AChE activity in thymic nerve fibres. Preliminary administration of dexamethasone prevented the effects.

[The functional status of the immunocompetent cells in animals at different times after the chronic action of irradiation and heat]. / Funktsional'noe sostoianie immunokompetentnykh kletok u zhivotnykh v raznye sroki posle khronicheskogo deistviia oblucheniia i tepla.

The proliferative response of thymic and splenic cells and the production of interleukin-1 and interleukin-2 by splenocytes were studied a day, three and six months after 25-fold separate and combination radiation (total dose 0.5 Gy) and heat (37 degrees C, 4h). The proliferative activity of lymphocytes of both organs was found to enhance a day after heating. No changes were found three months later. The proliferative activity of thymocytes in rats exposed to radiation and combination of the two factors was inhibited after six months. The production of interleukin-1 was lowered after irradiation.

[Effects of pulmonary surfactant on the activity of interleukin-1 secreted by macrophages in normal state and in pulmonary fibrosis]. / Vliianie surfaktanta legkikh na aktivnost' interleikina-1, sekretiruemogo makrofagami v norme i pri pnevmofibrose.

The article deals with the study of the influence produced by pulmonary surfactant on the activity of interleukin-1 secreted by macrophages which were isolated from the lungs of Wistar male rats 3 weeks after they were given a one-time administration of bleomycin or sodium chloride isotonic solution. Under conditions of prostaglandin synthesis stimulated by lipopolysaccharides and simultaneously inhibited by indomethacin macrophages of the lungs with forming fibrosis secrete an increased amount of interleukin-1. Cultivation of macrophages isolated from fibrosis-affected lungs with surfactant was also accompanied by enhanced activity of this monokine. Interleukin-1 secretion by macrophages of animals with fibrosis was drastically increased in the presence of polymyxin B. Under the same conditions pulmonary surfactant significantly stimulated the activity of monokine which was secreted both by cells of the normal animals and by those obtained from the lungs with fibrosis. Consideration is given to the importance of this phenomenon for the pathogenesis of pulmonary fibrosis.

[Antipyrogenic properties of oxytocin]. / Antipirogennye svoistva oksitotsina.

Effects of oxytocin on pyrogenal or endogenous pyrogen-induced fever were studied. Intramuscular injection of oxytocin (0.2 micrograms/kg every half an hour) did not significantly affect the pattern of pyrogenal-induced fever. Constant intravenous injection of oxytocin (0.4 and 4 micrograms/kg/h) 2-4.5 h after pyrogenal decreased the rectal temperature, on an average, by 24% and 31%, respectively. Endogenous pyrogen fever was not attenuated by intravenous oxytocin (4 micrograms/kg/h). The antipyrogenic effect of oxytocin is related to inhibition of endogenous pyrogen synthesis rather than to blockade of its action, which is indicated by a decreased second peak of the temperature curve, inhibition of endogenous pyrogen synthesis in vitro, and persistence of the hyperthermic effect of endogenous pyrogen.