[An effect of mexidol on the level of corsticosteron in the blood serum and beam zone cells in rats with light desynhronizes and physical loads]. / Vliyanie meksidola na uroven' kortikosterona v syvorotke krovi i kletki puchkovoi zony kory nadpochechnikov u krys pri svetovykh desinkhronozakh i fizicheskikh nagruzkakh.

OBJECTIVE: In order to develop methods and means of maintaining normal human functioning under conditions of desynchronizes, the effect of mexidol on the level of corticosterone in the blood serum and the state of the cells of the beam zone of the adrenal cortex of rats after light or dark deprivation and physical activity to a state of fatigue. MATERIALS AND METHODS: The experiments were performed on 7 groups of rats (10 animals each) in the spring. The model of physical activity is the method of forced swimming of rats until exhaustion in its own modification. For the induction of experimental desynchronizes, the animals of the experimental groups were kept around the clock for 10 days with artificial bright light of 150 LX or a complete darkening of 2-3 LX. Mexidol was administered intramuscularly at a dose of 10 mg/kg animal 30 minutes before the swimming test. Control animals under similar conditions were administered 0.9% sodium chloride solution. The level of corticosterone in the serum was determined using enzyme immunoassay. The measurements were carried out on a programmable photometer for STAR FAX 303 PLUS microsamples (USA). Histological analysis of the adrenal glands was carried out according to standard methods. Microscopy of preparations, imaging and measurements were carried out using an Axio Lab A1 microscope, an AxioCamERc 5s camera and ZEN 2012 software («Carl Zeiss Microscopy¼, Germany). Statistical processing of the results was carried out using standard parametric and non-parametric methods, depending on the nature of the distributions. RESULTS AND CONCLUSION: Mexidol under combined successive stress loads - desynchronizes and physical activity - demonstrated anti-stress properties not only at the level of corticosterone in the blood serum of rats, but also at the level of adrenal glands. The severity of this effect of the drug depended on the number of stress loads (isolated physical or shown in conditions of desynchronizes), the phase of stress and the nature of deprivation. Under natural lighting conditions and after light deprivation, when animals were in the anxiety phase of varying severity, the drug worked more reliably than after dark deprivation in conditions of developing depletion. Nevertheless, even in the latter case, he showed himself as a means of preventing exhaustion in animals and the breakdown of adaptation.

Influence of Sialadenectomy on the Development of Spermatogenesis in Rats: Ultrastructural Characteristics of Spermatogenic Epithelium and Leydig Cells.

Sialadenectomy in young rats modifies the development of the spermatogenic and steroidogenic functions of the testes. Sialadenectomy causes ultrastructural changes in spermatogenic cells, sustentocytes, and Leydig cells that disappear by week 8 of the experiment due to realization of compensatory and adaptive mechanisms. The effects of endocrine factors of the greater salivary glands on the spermatogenic cells are realized directly and indirectly via interstitial endocrinocytes and sustentocytes.

Structure of Rat Testicles after Intravenous Injection of Nanosized Magnetite Particles.

The structure of the testicles was studied in adult rats in 120 days after a single intravenous injection of chitosan-modified (magnetic nanospheres) and lipid-modified (magnetoliposomes) nanosized magnetite particles. Perls histochemical reaction detected in the testicular interstitial connective tissue the cells which absorbed and accumulated magnetite nanoparticles. The dynamics of spermatogenesis index and the count of Perls+ cells in the rat testicles were traced throughout the experiment. The studied modified nanosized magnetite particles did not penetrate through the blood-testicle barrier in rats.

Rhythmoinotropic Response of Papillary Muscles in Rats with Different Severity of Postinfarction Cardiosclerosis.

We studied the dependence of post-rest positive inotropic response of isolated rat papillary muscles subjected to rhythmic stimulation on severity of postinfarction cardiosclerosis developed during 6 weeks after occlusion of the left descending coronary artery. The isolated papillary muscles were perfused with oxygenated Krebs-Henseleit solution and electrically stimulated at a rate of 0.5 Hz. In all rats, coronary occlusion provoked postinfarction cardiosclerosis with the formation of a scar occupying 20-50% (min-max of the sample) of the left ventricular wall. Despite the presence of large postinfarction scar in all rats, the positive post-rest inotropic responses greatly varied. The post-rest response in rats with scar occupying <37% left ventricular wall was similar to that in intact animals, but rats with scar area >44% demonstrated dramatically decreased inotropic response to rest periods.

[Simultaneous magnetic resonance angiographic and tomographic assessment of atherosclerotic plaques of carotid arteries with paramagnetic contrasting by cyclomang].

The authors studied a possibility of simultaneously performing magnetic resonance (MR) angiography of carotid arteries and contrast-enhanced MR tomography of atherosclerotic plaques of carotid arteries. We examined a total of 16 patients presenting with disseminated atherosclerosis and 8 patients of the control group. Quadrature coils for examination of the head were used in order to sequentially perform MR tomography of the brain, MR angiography of carotid arteries and MR tomography of atherosclerotic plaques of carotid arteries with contrasting by 0.5M cyclomang. Angiography was carried out by means of the technique of 3D GR FFE of rapid gradient echo (TR/TE/FA/ST=10 ms/2.7 ms/20°/1.5 mm). MR tomography of the carotid arteries bifurcation was performed in the T1-weighted spin-echo mode: TR=500-900 ms, TE=10 ms, slice sickness 1-3 mm into the matrix 256x256 voxels, with the voxel size measuring 0.2x0.2x2 mm. The average time of passing of the paramagnetic through the blood vessels of the cerebral hemispheres in the control group amounted to 4.23±0.14 s for the left hemisphere and to 4.27±0.15 s for the right one. The mean time of bolus passing in patients with predominantly unilateral stenosis of the internal carotid artery amounted to 4.89±0.23 on the affected side, equalling 4.56±0.19 s on the unaffected side (p>0.05). In bilateral lesions these indices for the left and right hemispheres amounted to 4.98±0.21 s and 5.01±0.16 s (p>0.05), respectively. Contrast-enhanced MR angiography with cyclomang made it possible in all cases to visualize the localization and character of stenosis. The index of stenosis degree calculated for MR-angiogram highly significantly correlated with the indices of the ultrasonographic examination performed according to the ECST technique both for cases of unilateral (r=0.87, p<0.05) and cases of bilateral stenotic lesion (r=0.85, p<0.05). Inhomogeneous soft plaques with high content of lipids had high values of the enhancement index on contrasting--1.26±0.07, whereas hard fibrous avascular plaques--1.09±0.04 (p<0.05). The total time of the examination amounted to 41±5 min while performing time-fly MR-angiography and to 29±5 min without it. A conclusion was made that simultaneous MR angiography and contrast-enhanced (with Mn-paramagnetic) MR tomography of carotid arteries is possible and appropriate within the framework of a single study using quadratic coil for the head.

Cell-free collagen-based scaffolds used for making blood vessels in cardiovascular surgery.

The present article deals with the technology of obtaining decellularized cell-free collagen-based scaffolds from arterial vessels and surgical assessment of the possibility of experimentally implanting them into the blood system of laboratory animals for experimental purposes. The study was performed on arterial vessels (n=60) and fragments of the human internal thoracic artery (n=20). Described herein is a method of obtaining a connective-tissue matrix of a blood vessel by means of vessel's perfusion for 2-3 hours with detergent solutions. Cell-free collagen-based conduits were implanted to a total of ten dogs. After the operation, the blood flow remained functional. The anastomoses established turned out to be leak-proof and the acellular vessels were able to withstand the haemodynamic load of the arterial blood flow.