Effect of paraoxon and sulfhydryl reagents on3H-quinuclidinol benzoate and3H-methylscopolamine with synaptic membranes of rat brain

Paraoxon is shown to reduce the density of M-choline receptors in the cortex of rat brain. Inhibition of³H-QNB is noncompetitive and reversible in nature. Sulfhydryl reagents do not affect this process. The mechanism of action of PO is thought to include direct effects on brain muscarine receptors. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 51–53, July, 1994     

The effect of morphine on RNA synthesis in some brain structures of rats with various narcological resistance

Different incorporation of³H-uridine in RNA and increased RNA synthesis after the addition of morphine are demonstrated in all brain structures of resistant rats, as well as in the cortex, nucleus accumbens, griseum centrale, and nucleus ventriculus hypothalami of prone rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 100–102, January, 1994     

Opioid peptides improve human fetal nervous tissue survival after cryopreservation in culture

The study was carried out on the 18–20-week human fetal brain by culturing organotypic and dissociated cells of the cerebral cortex and the corpora quadrigemina area. Tissue viability was assessed from the formation of growth cones and neuroglial bundles, as well as of glial cell formation. The study showed that after tissue freezing in organotypic cultures, viable cells were detected in not more than 10% of grafts. The addition of opioid peptides noticeably (by 1.3–2 times) increased the number of surviving cells. This regularity was not observed in dissociated cultures. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 4, pp. 408–411, April, 1994     

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     

Some cytochemical peculiarities of the rat brain motor system after space flight

The results of cytochemical cytometry of rat brain suggest that a 9-day exposure of rats to microgravitation conditions lowers the activity of monoaminoxidase in the fibrous structures of layer V of the somatosensory cortex and in the head ofnucleus caudatus, as well as the activity of acetylcholine esterase in the bodies of neurons forming the head ofn. caudatus. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 288–290, March, 1995 Presented by the late O. S. Adrianov, Member of the Russian Academy of Medical Sciences     

Effect of picrotoxin and bicuculline on desensitization of the GABA receptor/Cl− ionophore complex

A study is performed of the effect of the convulsants picrotoxin and bicuculline, blockers of GABA-dependent Cl⁻-conductivity, on the rate of desensitization of muscimol-induced³⁶Cl⁻ entry into synaptoneurosomes isolated from rat cortex. Both picrotoxin and bicuculline, despite the difference in the mechanisms of inhibition of the GABA receptor/Cl⁻ ionophore complex, markedly reduce the rate of desensitization. However, the initial moment of the action of both convulsants is characterized by inhibition of Cl⁻ transport alone, without a drop of the rate of desensitization. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 8, pp. 160–163, August, 1994     

Effect of transplantation of human fetal tissue on central nervous system function in patients with the postcastration syndrome

Electrical activity of the brain was studied in 45 women after total oophorectomy in a state of calm alertness and in functional overload before and after transplantation of human fetal tissues. Pretransplantation studies showed α-rhythm disorganization, α-activity polyrhythmicity, a tendency toward high-frequency rhythms, and a disordered process of internal synchronization. Studies carried out after human fetal tissue transplantation showed adjustment of the cortex-stem relationships, a reduction of the α-rhythm index, and an increased β-activity index. Reactions to light stimuli and the function of the cerebral cortex improved in the majority of patients after transplantation, this being manifested in appropriate reactions to afferent stimulation. However, by the 6th month posttransplantation electrical activity of the brain was virtually the same as pretreatment. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 4, pp. 382–385, April, 1994     

Mice selected for low brain weight show heightened sensitivity to the convulsive action of pentylenetetrazole

Convulsive activity of pentylenetetrazole (25–120 mg/kg) measured in mice selected for large or small brain weight was evaluated, and mice with a smaller brain weight proved to be more susceptible to the damaging action of this compound than those with a larger weight. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 460–462, May, 1995 Presented by V. S. Rusinov, Member of the Russian Academy of Medical 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     

Effect of stress on the reticular zone of the adrenal cortex

The reticular zone (RZ) of the adrenal cortex is shown to be involved in the formation of the organism's response to stress. A new scheme of physiological regulation of RZ is presented. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 118, N ^o 7, pp. 8–10, July, 1994 Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences     

Binding of3H-diazepam in rat brain eleven months after termination of corazole kindling

Binding of³H-diazepam in rat cerebellum decreases by 14% (p<0.05) 11 months after termination of kindling and one day after injection of a test dose of corazole (30 mg/kg), while it increases by 19.5% after a single injection of a convulsive dose of corazole (50–75 mg/kg). No changes are found in the cortex. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 2, pp. 135–137, February, 1994 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Activity of NO-synthase and radical formation in rat brain compartments: Age dependence

The relationship between age and the activity of NO-synthase and generation of free radicals in different compartments of the brain was studied in male Wistar rats. No-synthase activity was highest in the cerebellum and lower in the cerebral cortex. It increased with age in the cerebellum and remained unchanged in the cortex, being virtually the same in the right and left hemispheres. Radical generation was much higher in the cerebellum than in the cortex and, as a rule, was age-dependent. The ratio of NO-synthase activity to radical generation was age-dependent: a tendency toward a positive linear correlation was observed in young animals, no correlation could be traced in adults, and a negative one was observed in old rats. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120, N ^o 7, pp. 54–56, July, 1995 Presented by I. P. Ashmarin, Member of the Russian Academy of Medical Sciences     

Different effects of glucocorticoids on the density of β-adrenoreceptors in the lungs and cerebral cortex

Tissue specificity of the effect of glucocorticoids on the density of β-adrenoreceptors is shown. The hormone increases the number of receptors in the lungs, but has no effect on their density in the cerebral cortex either in the norm or after down-regulation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 328–330, March, 1995 Presented by V. A. Trufakin, Member of the Russian Academy of Medical Sciences     

Microwave-induced changes in synaptoarchitectonics at different levels of the visual analyzer

It is shown that interneuronal bonds at different levels of the visual analyzer are highly sensitive to microwaves (60 mW/cm², 10 min). Evidence of this is seen from the early degeneration and reduced numerical density of synapses and, in the cortical substance, in the reduced total length of active zones of contacts. The rate of recovery of the synaptic apparatus decreases in the following order: retina→external geniculate bodies→visual cortex. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 219–222, February, 1996 Presented by E. D. Gol'dberg, Member of the Russian Academy of Medical Sciences     

Informational capacity of the rat sensorimotor cortex in the postresuscitation period (morphometric analysis of a neuronal population)

The number of neurons was counted in different functional neuronal complexes of the sensorimotor cortex in albino rats in the control and at different times after clinical death caused by asphyxia. A decrease of the number of neurons from 2.5×10⁶ in the control to 1.56×10⁶ toward the 30th day of the postresuscitation period was found in the sensorimotor cortex. The complexes of small neurons in the upper floor (layers II–IV) suffer badly, while the neurons of layer VI are damaged to a somewhat lesser degree and the cells of layer V are minimally altered. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 3, pp. 331–333, March, 1995 Presented by L. V. Poluektov, Member of the Russian Academy of Medical Sciences     

Ultrastructural reorganizations of synaptic contacts in an organotypic culture of the brain cortex in the presence of ethanol

The effect of various ethanol concentrations (0.5 and 1%) on the ultrastructure of interneouronal contacts is studied in an organotypic culture of the brain cortex from newborn rats. It is shown that ethanol in the culture medium causes geometric complications in the synaptic contacts. Morphometric analysis of synapses reveals an increase of the area and perimeter of axon terminals and of the length of the active zone of the contact, as well as a decrease of the coefficient determined by the ratio of the number of synaptic vesicles to the length of the active zone of the contact. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 120 N ^o 7, pp. 99–102, July, 1995 Presented by V. Ya. Semke, Member of the Russian Academy of Medical Sciences.     

Spontaneous activity and evoked potentials in the caudal trigeminal nucleus,ventrobasal thalamus,and cerebral cortex of rats with neuropathic trigeminal neuralgia

Incomplete compression of the infraorbital nerve in rats leads to spontaneous neuronal activity in the form of bursts in the caudal trigeminal nucleus and to epileptiform activity in the ventrobasal thalamus and cerebral cortex. From the latter, afterdischarges are also recorded. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 117, N ^o 1, pp. 26–29, January, 1994     

The new technology of hot start polymerase chain reaction

The use of monoclonal antibodies against Taq DNA polymerase in the polymerase chain reaction is proposed. These antibodies effectively inhibit polymerase activity at temperatures <70°C, activity being restored upon DNA melting in the very first stage of amplification. As in the “hot start” reaction, the addition of the antibodies to the incubation medium markedly improves the reaction yield. The method is particularly effective for the identification of a few copies of DNA. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 121, N ^o 2, pp. 238–240, February, 1996 Presented by V. N. Smirnov, Member of the Russian Academy of Medical Sciences     

Patterns of homeostatic alterations during delayed aftereffects of radiation: Detection using laser correlation spectroscopy

Identification of the subfraction composition is performed using the method of laser correlation spectroscopy, which makes it possible to estimate the contribution of 1–10⁴-nm particles in the total effect of quasi-elastic light scattering. Special classification software is used to analyze statistically the complex multicomponent spectra, bringing to light reliable shifts differentiating the pathological processes. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o 5, pp. 556–560, May, 1995 Presented by G. N. Kryzhanovskii, Member of the Russian Academy of Medical Sciences     

Effect of bromantane,a new immunostimulating agent with psychostimulating activity,on the release and metabolism of dopamine in the striatum of freely moving rats. A microdialysis study

It is demonstrated that bromantane induces a pronounced and prolonged (8 h) increase in the release of dopanime. Tetrodotoxin (10⁻⁶ M) perfused via a microdialysis probe partially inhibits the bromantane-induced release of dopamine. The extracellular content of the dopamine metabolites 3,4-dioxyphenylacetic and homovanillic acids is slightly decreased. The possible mechanisms of action of bromantane on the dopamin- and serotoninergic systems of the brain are discussed. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 119, N ^o . 3, pp. 302–304, March, 1995 Presented by M. D. Mashkovskii, Member of the Russian Academy of Medical Sciences