Effects of serotonin-IA receptors on amino acid and dopaminergic responses of neurons]

By using intracellular technique the authors studied the responses of frog spinal motoneurones and rat dorsal root ganglion evoked by GABA, L-aspartate and dopamine in the presence of 5-hydroxytryptamine and its 1A-agonists or without them. It is shown that buspirone, campirone and serotonin increase the GABA effects but inhibit the effects of aspartate via the GABA- and NMDA-receptors modulation.     

Method for the quantitative evaluation of the effect of drugs and other factors on the viability of an ischemic skin flap

The use of a skin graft from the leg or back of mice or rats (10 X 20 mm) or rats (12 X 52 mm) with its further packing results in the 50 +/- 10% ruin of the distal part. The effect of different factors on necrosis change in size is quantitatively evaluated.     

Experimental study of the pulmonary form of plague, tularemia and pseudotuberculosis]

There was revealed a regular reduction of plague, tularemia and pseudotuberculosis bacteria count in the lungs of guinea pigs the first 12 hours after aerosol infection. Generalization of the infectious process and associated septicemia occurred in pulmonary plague and pulmonary tularemia on the 1st-2nd day, and in pulmonary pseudotuberculosis - on the 4th-5th day. Limits of accumulation of the causative agents in the organs and the blood at various stages of the infectious process were established.     

Use of excimerization of pyrene for assessing lipid microviscosity in biological membranes]

A method for estimating the fluidity of natural membranes from the pyrene excimer/monomer fluorescence ratio (Ie/Im) is proposed. The method makes it possible to exclude artefacts such as fluorescence quenching, aggregation, and redistribution of the probe in lipid mains with different microviscosity. It is shown that, upon variation of intramembrane pyrene concentration [pyr], the occurrence of a common crossover point in pyrene fluorescence spectra normalized to the corresponding probe concentration (isoemission or isobestic point) or, as a consequence, the linear dependence of Ie/[pyr] on Im/[pyr] can serve as a criterion of diffusion (fluidity)-controlled excimerization of pyrene. The isobestic point can be used for determining the range of working concentrations of the probe in membrane suspension. It was found from the intensity of pyrene fluorescence in the isobestic point and quenching with potassium iodide that at t < 30 degrees C, the probe is uniformly distributed throughout the membrane, and its excimerization is mainly controlled by the microviscosity of environment.     

Involvement of the intracellular regulatory systems in the adaptive effect of short-term anoxia in vitro]

Moderate long-term activation of intracellular regulatory system (IRS) was found to be manifested as an increase in the bound calcium content and intensity of the phosphoinositide metabolism following a 30-minute re-oxygenation in the rat olfactory cortex perfused slices. The perfusate induced a similar activation in intact slices-recipients. Long-term anoxia induced a biphasic NMDA-dependent increase in intracellular free Ca2+ and pathogenic hyperactivity of the IRS. The pathogenic events could be prevented by preconditioning of the slices by either short-term anoxia (STA) or post-STA donor perfusate.     

Extracellular vesicle-mediated transfer of membranous components from the highly malignant T24 urinary carcinoma cell line to the non-malignant RT4 urinary papilloma cell line

This communication reports the first experimental evidence that in the bladder cancer model, membranous components labelled with the DiO dye and the cholera toxin subunit B can be transported from highly malignant (T24) to non-malignant (RT4) cells by extracellular vesicles. Taking into account the presence of stable membranous nanostructures found by scanning electron microscopy, we suggest a possible uptake mechanism in recipient cells through fusion with highly curved membranous regions.     

Growth-stimulating effect of UF-irradiated blood. I. The radiation dose dependence of the initial growth potencies of blood and of the functional state of the target cells

UV irradiation (UVI) of donor blood in the apparatus used in hospitals of the USSR with the therapeutic aim of autotransfusion of UV-irradiated blood (AUVIB), results in an increase of connective tissue cell growth potency: being added into culture media the supernatants of irradiated blood stimulate DNA-synthetic and proliferative activity of cultured human embryonic cells. The high activity of cells persists for about 2 days. The effect is great with low initial levels of cell proliferative activity. In this case the effect is maximum (about 125% of the control). It is suggested that the above effect may be involved in the mechanism of stimulation of regeneration processes in the organism after AUVIB.