[Influence of 900 MHz frequency electromagnetic radiation on some blood indices].

The paper represents the results of research of some functional indices of blood plasma and erythrocytes in rats obtained on days 1 and 5 after exposure of the organism to low intensive electromagnetic irradiation (EMI) with 900 MHz frequency using the following two irradiation schemes: single 2 h/1 day and fractional 0.5 h/4 days. According to the data obtained, a significant increase of lipid peroxidation (LPO) intensity is registered in animal erythrocyte membranes after the influence of 900 MHz frequency EMI irrespective of the scheme applied. Inhibition of the activity of low-molecular non-enzymatic water-soluble blood antioxidants and enhancement of blood plasma LPO processes is observed on the background of a single prolonged exposure. Stimulation of the antioxidant activity with an abrupt decrease in the blood LPO activity takes place after exposure to fractional irradiation. Single long-lasting exposure, rather than intermittent shortterm exposure to 900 MHz frequency EMI facilitates the appearance of shifts in the activity of Ca(2+)-dependent K(+)-channels of erythrocytes and hyperpolarization of erythrocytes membranes.

[The influence of aromatic amino acid derivatives on the complement system under ionizing radiation].

Activities of the complement classical, alternative and lectin pathways were determined under conditions of X-radiation in the blood of rats treated and none-treated with synthetic Schiffbase aromatic amino acid derivatives, nicotinyl-L-tyrosinate or nicotinyl-L-tryptophanate, before irradiation. In case of activities of the alternative and lectin pathways no significant changes between irradiated animals and none-irradiated control animals were detected. However, the data obtained demonstrate significantly elevated activity of the classical complement cascade in the blood of irradiated animals (1 day after irradiation), as compared to those none-irradiated. This effect was less pronounced in rats treated with nicotinyl-L-tyrosinate or nicotinyl-L-tryptophanate 1 hour before irradiation. Based on the results obtained the ability of nicotinyl-L-tyrosinate and nicotinyl-L-tryptophanate to act as cyto-protectors is concluded.

[Modifying action of Mn(II) chelate with ethyl ester of salicylydene tyrosine on some biophysical parameters of erythrocyte membranes of the irradiated organism]. / Modifitsiruiushchee deistvie khelata Mn(II) s étilovym éfirom salitsiliden-tirozina na nekotorye biofizicheskie parametry éritrotsitarnykh membran obluchennogo organizma.

The presentation summarizes the results of studies on radioprotective activity of newly synthesized Mn(II) chelate with ethyl ester of salicylydene D,L-tyrosine, basing on the evaluation of its membrane-protective effects, revealed at different periods post the exposure of the organism to ionizing radiation. It was revealed that the administration of the compound into the animal organism before the radiation exposure (gamma-irradiation of 60Co at a dose level of 4.8 Gy) produced correcting action on structure-functional properties of erythrocyte membrane of irradiated rats: the excessive activation of lipid peroxidation of erythrocyte membranes was inhibited, the passive permeability of erythrocytes for K+ ions was normalized, the deformity and membrane potential of erythrocytes according to hydrogen-chlorine gradient were recovered.

[Electromagnetic fields of millimeter range: effect on the structure and functional properties of erythrocyte membranes]. / Vozdeistvie élektromagnitnykh polei millimetrovogo diapazona na strukturno-funktsional'nye svoistva éritrotsitarnykh membran.

The effect of coherent and non-coherent electromagnetic fields of millimetre range on biophysical and biochemical indices of blood erythrocytes and plasma of the animals totally exposed to radiation at various periods of observation (day 1, 5, 10) was studied. The following structure-functional shifts were revealed: deviations in the content of separate phospholipid fractions of erythrocyte membranes, the changes of lipid peroxidation products in erythrocyte membranes and blood plasma of the irradiated animals, statistically significant increase of K ions out-flow from the erythrocytes, as well as the alteration of the value of membrane potential of erythrocytes.

[The antiarrhythmic action of piracetam]. / Nekotorye aspekty antiaritmicheskogo deistviia piratsetama.

It was found that a drug of the nootropic nature piracetam possessing pronounced antihypoxic properties eliminates calcium chloride-induced disturbances of the cardiac rhythm and significantly raises the threshold of atrial fibrillation during electrical stimulation. The drug's antiarrhythmic effect is followed by a decrease of the rhythm rate and an increase of the contraction amplitude. The animals treated with piracetam in a dose when its antiarrhythmic effects (300 mg/kg) exhibited a decrease of the membrane potential of erythrocytes as compared with control. Similar effects occurred in the animals treated with lidocaine. It can be concluded that in certain types of arrhythmias the use of piracetam restores the normal rhythm of contractions that is perhaps connected with its positive influence on metabolic processes in the myocardium.