Anti-ischemic effect of a new oxynicotinic acid derivative

The effect of a new derivative of oxynicotinic acid (KONA) on experimental cerebral ischemia is examined in rats. It is demonstrated that a single dose of the preparation (30 mg/kg) significantly decreases the severity of ischemic damage and increases the survival of the animals after bilateral ligation of the common carotid arteries. Comparison with xanthinol-nicotinate shows the advantages of the new preparation. Although KONA does not inhibit free-radical oxidationin vitro, it does lower the content of free-radical oxidation products in rat blood plasma to the normal level. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 49–51, July, 1994 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Karyometric analysis of hepatocytes of common field mice from regions with different levels of technogenic contamination

Increased polyploidy of hepatocytes is shown using karyometric analysis in common field mice from different Altai regions with high levels of technogenic contamination of radiation and chemical nature. A higher degree of polyploidy is noted in animals with more marked alterations in hepatocytes classified as dystrophic and necrobiotic. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 223–227, February, 1996 Presented by D. S. Sarkisov, Member of the Russian Academy of Medical Sciences     

Structural and functional changes in the brain of rats with different behavioral types at later stages of circulatory hypoxia

Structural changes in the brain were studied at later (one and three months) stages of cerebral hypoxia caused by occlusion of the common carotid arteries, which were indicative of the development of recovery and destructive processes. Brain ultrastructure was found to be better preserved in rats with an active type of behavior one month after the onset of ischemia than in rats of the other groups; motor activity was restored to the baseline level, thus demonstrating a higher rate of recovery processes. Significant ultrastructural damage to the brain at the same stage of ischemia was observed in rats with a passive type of behavior (especially in rats of the middle group), while motor activity was increased. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 529–534, November, 1994 Presented by P. V. Simonov, Member of the Russian Academy of Sciences     

Effect of opioid lymphostimulation on the microcirculation in pial vessels of the ischemized rat brain

The response of pial vessels to i.p. administration of leu-enkephalin (at 40 μg/kg) is studied biomicroscopically in the control, before and after bilateral occlusion of the common carotid arteries. Leu-enkephalin causes chiefly the narrowing of pial arterioles and does not affect venule diameter. The effect of leu-enkephalin on occlusion of the common carotid arteries manifests itself in the preservation of circulation stability, the narrowing of some arterioles, and in the decrease of the degree of dilation. These changes occur against the background of lowered arterial pressure, bradycardia, increased local circulation in the brain cortex by 50–70%, intensification of the lymph flow in micro- and macrovessels, and the absence of mortality of animals in the first hours of occlusion of the arteries. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 100–105, January, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Analysis of changes in the electroencephalogram power spectrum on a new model of brain ischemia in rats

The bioelectrical activity is studied in the left and right parietal cortex by recording the power spectrum of the electroencephalogram in brain ischemia caused by complete ligation of the left common carotid artery and 50% reduction of the blood flow in the right common carotid artery in experiments carried out on nonnarcotized Wistar rats. Ischemia results in marked and stable disorders in the bioelectrical activity manifested in a decrease of the total EEG power, depression of the dominating frequency in the Θ-range, increase of the δ-range power, and interhemispheric asymmetry of some spectrogram parameters. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny Vol. 118, N ^o 12, pp. 565–567, December, 1994 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Effect of nimodipine on the circulation in the midbrain and carotid arteries of rats

It is found that nimodipine induces biphasic changes in the circulation in the midbrain artery: an initial slight and transient reduction gives way to a considerable and long-term increase of the circulation. Nimodipine also boosts the circulation in the common and internal carotid arteries, which coincides in time with, but is shorter than, the first phase of changes in the hemodynamics in the midbrain artery. The findings are not consistent with the common view on the selectivity of the cerebrovascular effect of nimodipine. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 10, pp. 410–413, October, 1994 Presented by M. D. Mashkovskii, Member of the Russian Academy of Medical Sciences     

Reactivity of capillaries and pyramidal neurons in rat cortex under conditions of acutely reduced circulation

A study of capillaries and pyramidal neurons of the cortex in white rats subjected to ligation of the common carotid artery reveals that acute reduction of the circulation is characterized by a decreased activity of alkaline phosphatase and Na, K-ATPase as well as a reduced number of capillaries marked with these enzymes, and a lower activity of butyrylcholine esterase. A decreased activity of cytochrome oxidase in neurons suggests the existence of intracellular compensatory-adaptive mechanisms. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 558–560, May, 1994 Presented by O. S. Adrianov, Member of the Russian Academy of Medical Sciences     

Effect of the organophosphorus pesticide anthio on the blood supply to the brain

Experiments with cats using ultrasound shown that exposure to the organophosphorus compound Anthio leads to a reduction of vascular resistance of the carotid and internal maxillary arteries. The bloodflow in these arteries does not decrease for a long time. The share of bloodflow in the internal maxillary artery is increased vis-a-vis the total flow in the carotid artery. A reduction of the blood supply to the brain is observed only by the end of the experiment witb a blood pressure of 40 to 50 mm Hg. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 270–275, March, 1995 Presented by N. A. Agadzhanyan, Member of the Russian Academy of Medical Sciences     

The microcirculatory bed of hamster cheek pouches after occlusion of the common carotid arteries

The responses of hamster cheek pouch microvessels after occlusion of the common carotid artery on the ipsilateral side are compared. It is found that under conditions of limited inflow the microvessels preserve the inflow on the left side and the outflow on the right side, with venular constriction predominating in the left cheek and arteriolar in the right. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 144–147, February, 1996 Presented by V. V. Kupriyanov, Member of the Russian Academy of Medical Sciences)     

Microcirculatory disturbances in rat brain upon neurosis

In vivo study of the microcirculation in the basin of the midbrain artery of neurotized rats by means of biomicroscopy demonstrated changes in arteriole form and interruption of blood flow in venules. Bilateral occlusion of the common carotid arteries led to the dilation of all observed arterioles in control rats. The response to occlusion in neurotized animals was found to be as follows: 54% of arterioles showed dilation, 21% showed constriction, and 25% did not change in diameter. Constriction was observed in 59% of studied venules, while 41% of venules did not change in diameter. Interruption of blood flow in venules was observed in some cases. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 11, pp. 521–522, November, 1994 Presented by V. S. Rusinov, Member of the Russian Academy of Medical Sciences     

Comparative morphometric and information analysis of the changes in different parts of the pancreas following ligation

The compensatory-adaptive changes in the guinea pig exocrine and endocrine pancreas following ligation are studied using morphometric and information methods. Objective criteria for evaluating organ changes are elaborated. The specific features of regeneration in exocrine and endocrine parts of the organ are described. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 1, pp. 86–88, January, 1995     

Effect of hemodilution and hemoconcentration on postischemic alterations of microvessels in rabbit paired auricles

Morphometric parameters of microvessels in paired rabbit ears and blood sampled from the internal vein were studied after ischemia reproduced under conditions of prior hemodilution and hemoconcentration. In hemodilution the postischemic alterations were found to be more pronounced in microvessels of the left ear, while for the right the same was true for rheological characteristics of the outflowing blood. Under conditions of hemoconcentration after ischemia the changes in rheological indexes were more marked on the left and in vasomotor indexes on the right. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 352–354, March, 1996 Presented by V. V. Kupriyanov, Member of the Russian Academy of Medical Sciences     

Pathomorphological investigation of feline lungs in modeled pneumonia

The nature and specificity of the damaging effect of an Anthio-tarred turpentine combination and the changes it produces are studied in acute, subacute, and chronic experiments on cats. Anthio, a compound capable accumulating in adipose tissues and destroying lipid-containing structures (for example, surfactant), induces characteristic destructive effects on lung alveoli and causes dystelectasis and the formation of ectases, which are observed in acute experiments. The ectases contain an oxyphilic serous exudate and microfocal lymphoid-cellular clusters in the alveolar wall and are characterized by microcirculatory disorders such as edema, capillary and venous stases, and microhemorrhages. Study of the combined effect of Anthio and turpentine shows that the Anthio-induced destruction is persistent and probably creates conditions for secondary damaging factors which aggravate the pathological process and broaden the spectrum of the morphological alterations characteristic of acute pneumonia. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 1, pp. 103–107, January, 1996 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Pathomorphologic investigation of intraorgan arteries in patients with coarctation of the aorta

A stereotypic angiospasm develops in intraorganic arteries during coarctation of the aorta, which is characterized by different functional impacts: resistance in the basin of elevated vascular pressure and pressure and bloodflow regulation in the hypotension basin. The most marked structural changes are observed in the renal and coronary arteries. Changes in the small coronary arteries are mainly due to myocardial hypertrophy, whereas in the larger ones they are caused by the increased pressure transferred from the aorta. The degree of structural changes in the larger coronary arteries is greater than in the small arteries. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 3, pp. 332–336, March, 1995     

Impact of preliminary gamma-irradiation on the pattern of change in vascular tone after intravenous injection ofNeisseria meningitidis lipopolysaccharide in rats

It is shown on rats that intravenous administration of theNeisseria menignitidis lipopolysaccharide lowers the mean arterial pressure, myocardial contractility and vascular tone in the system of the left carotid artery. In rats exposed to gamma radiation and then to the lipopolysaccharide, the decrease in myocardial contractility and the degree of arterial hypotension were more pronounced than in those exposed to the lipopolysaccharide alone, but the vascular tone in the carotid artery system was reduced to a lesser extent. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 129–131, August, 1995 Presented by V. A. Matyukhin, Member of the Russian Academy of Medical Sciences     

Antithrombogenic effect of urokinase bound to collagen substrate with bifunctional antibodies

In vitro experiments simulating collagen-induced thrombogenesis in arteries damaged during angioplasty demonstrate a marked inhibitory effect of surface-bound urokinase. In contrast to free urokinase, bound enzyme is more effective in preventing platelet aggregation on the collagen surface. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 5, pp. 504–507, May, 1994 Presented by V. N. Smirnov, Member of the Russian Academy of Medical Sciences     

Ultrastructural stereological analysis of absolute parameters of cardiomyocytes exposed to contrasting temperature effects

It is shown that moderate low and superlow temperatures as well as general overheating of the organism cause a marked decrease in the total volume of mitochondria and sarcoplasmic matrix in cardiomyocytes of the left ventricle. These alterations develop in all cases and do not depend on changes (an increase or decrease) in the heart mass. The most pronounced alterations in the total volume and area of the main organelles of cardiomyocytes are noted after general cooling of the organism. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp 437–441, October, 1995 Presented by V. V. Lyakhovich, Member of the Russian Academy of Medical Sciences     

Effects of chitosan on the biological properties of gram-negative bacteria endotoxins

The destructive action of Gram-negative bacteria lipopolysaccharides and their complexes with chitosan, a natural polycation, was comparedin vivo andin vitro. Lipopolysaccharides in complex with chitosan modified the biological properties of endotoxin, among other things, reducing its toxic and aggregation effects. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 8, pp. 169–172, August, 1995 Presented by V. I. Pokrovskii, Member of the Russian Academy of Medical Sciences     

Morphofunctional changes in the intima of collateral arteries in modeled aorta coarctation

In modeled aorta coarctation long-term functioning of collateral arteries is shown to be accompanied by activation of subintimal smooth muscle cells and elastofibrosis of the intima, which are a manifestation of hemodynamic arteriosclerosis. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 82–85, July, 1994 Presented by L. D. Sidorova, Member of the Russian Academy of Medical Sciences     

Ion transport and its adrenergic regulation in erythrocyte membranes of the breamabramis brama injected with a mixture of polychlorinated biphenyls

In the first 10 days after the injection of Sovol-54 (a mixture of chlorinated biphenyls) into the breamAbramis brama, considerable alterations in the hormonal regulation of cotranport were observed for erythrocytes of this fish, along with an increase in the passive permeability of their membranes. No significant changes were recorded in Na⁺, K⁺-ATPase activity or its adrenergic regulation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 10, pp. 379–381, October, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences