Active avoidance without discrimination control as model for studying the protective action of drugs in emotional stress

By plotting histograms of distribution of the frequency of intervals between pressing a lever (the active-avoidance method without discrimination control) it is possible to assess fine changes in the character of operant activity arising in rats through emotional stress. The design of a simple multichannel apparatus for inducing and studying active avoidance in several animals is described.Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 10, pp. 500–501, October, 1979.     

Autoradiographic localization of3H-GABA and3H-muscimol binding in rat cerebellar cultures

Summary Autoradiographic studies were conducted on the binding of³H-GABA and³H-muscimol in cultures of rat cerebellum. Binding sites for both substances were observed on many cerebellar neurones, such as Purkinje cells and interneurones, but not on glial cells. Binding of³H-GABA and³H-muscimol was inhibited by unlabelled GABA and by the GABA antagonist bicuculline.     

Effect of psychotropic drugs on behavior of inbred mice under emotional stress

The behavior of C57BL/6, CBA, and BALB/c mice in an open field test was studied after administration of phenazepam in doses of 0.05, 0.075, and 0.1 mg/kg and of sydnocarb in doses of 6, 12, and 24 mg/kg. The initial response to emotional stress was characterized by greatest motor activity (MA) in C57BL/6 mice and minimal in BALB/c mice. Phenazepam lowered MA in C57BL/6 mice proportionally to the dose. A biphasic effect of the tranquillizer was found in BALB/c mice. Depending on the dose, sydnocarb stimulated MA of C57BL/6 mice, did not effect the behavior of CBA mice, and in a dose of 24 mg/kg, it increased MA of BALB/c mice.Laboratory of Pharmacological Genetics, N. I. Pirogov Second Moscow Medical Institute. (Presented by Academician of the Academy of Medical Sciences of the USSR V. V. Zakusov.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 7, pp. 38–40, July, 1979.     

Activation of lipid peroxidation during painful emotional stress

Accumulation of primary and secondary lipid peroxidation (LPO) products were investigated by ultraviolet spectrophotometry and fluorescence of Schiff bases in various tissues of Wistar rats subjected to painful emotional stress (PES). The quantity of LPO products was shown to increase under the influence of PES mainly in the heart, and also significantly, although to a lesser degree than in the heart, in skeletal muscles and brain. The increase in content of hydroperoxides in all the organs studied was smaller than the increase in the content of fluorescent Schiff bases, the end products of LPO.Laboratory of Pathophysiology of the Heart, Institute of General Pathology and Pathological Physiology Academy of Medical Sciences of the USSR. Laboratory of Physical Chemistry of Biomembranes, M. V. Lomonosov Moscow University. Laboratory of Pathological Physiology, Institute of Psychiatry, Academy of Medical Sciences of the USSR, Moscow. (Presented by Academician of the Academy of Medical Sciences of the USSR A. M. Chernukh.) Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 88, No. 10, pp. 404–406, October, 1979.     

Autoradiographic localization of binding sites for 3H-serotonin and 3H-ketanserin on neurones and astrocytes of cultured rat brain stem and spinal cord

Summary By means of lightmicroscopic autoradiography we have studied the cellular localization of binding sites for ³H-serotonin and ³H-ketanserin in organotypic cultures of rat brain stem and spinal cord. In both types of cultures, a relatively great number of neurones revealed binding sites for ³H-serotonin which predominantly labels S₁-receptors. ³H-ketanserin, an S₂-antagonist was also bound to many neurones although to a lesser extent than ³H-serotonin. Binding sites for both radio-ligands were also observed on astrocytes. These findings together with electrophysiological investigations indicate that astrocytes possess serotonin receptors.     

Ontogeny of 3H-muscimol binding to membranes of chick forebrain

Summary A potent GABA agonist, ³H-muscimol, was used to investigate the development of GABA receptors in left and right hemispheres of chick forebrain from day 12 in ovo to day 21 post-hatch. Total specific ³H-muscimol binding (p mol mg^–1 protein) increases rapidly in ovo, reaching a peak at around day one post-hatch and then showing a slow decline to approximately 50% of the maximal level at day 21 post-hatch. Despite the considerable evidence from previous studies of lateralization of avain brain function, no significant hemispheric differences were found in ³H-muscimol binding (either of p mol hemisphere^–1 or p mol mg protein^–1) at any of the developmental ages examined.     

Role of brain stem in the mechanisms of individual resistance of rats to emotional stress

It is shown in rats that the structures of brain stem (medial and lateral nuclei) are involved in the mechanisms of individual resistance to emotional stress (immobilization and cutaneous electrostimulation). Bilateral destruction of brain stem structures reduces this resistance, which manifests itself as behavioral changes in the open field test (the behavior of rats resistant to stress resembles that of rats prone to it), increased adrenal hypertrophy, thymic involution, and high mortality under conditions of emotional stress. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 124, No. 11, pp. 501–505, November, 1997     

Effect of hydiphen on behavior and hemodynamic manifestations of emotional stress

Hydiphen is an original Soviet tranquilizer (diphenylphosphinylacetic acid hydrazide). In a dose of 120–150 mg/kg hydiphen restores the central baroreceptor reflex regulation of arterial pressure, when depressed in cats during an acute emotional-stress reaction (confrontation with a dog). The compound has an antihypertensive antiaggressive action, and does not induce ataxia. Behavior was investigated quantitatively in animals during group interaction, using a five-point system.Institute of Pharmacology, Academy of Medical Sciences of the USSR, Moscow. Department of Pharmacology, First Leningrad Medical Institute. Department of Pharmacology, S. V. Kurashov Kazan' Medical Institute, Translated from Byulleten' Éksperimental'noi Biologii i Meditsiny, Vol. 89, No. 3, pp. 310–312, March, 1980.     

Effect of benzodiazepines on synaptosomal Ca2+ transport in mice with different phenotype of emotional stress reactions

The effects of 5 benzodiazepines on basal and K⁺-induced Ca²⁺ concentration in synaptoneurosomes from intact and stressed C57B1/6 and BALB/c mice were studiedin vitro. Membrane depolarization induced by low KCl concentrations produced different effects on Ca²⁺ accumulation by synaptoneurosomes from two mouse strains. Benzodiazepines appliedin vitro exerted no effects on Ca²⁺ influx. In synaptoneurosomes from both C57B1/6 and BALB/c mice exposed to emotional stress diazepam in a dose of 5 mg/kg reduced the basal and K⁺-induced Ca²⁺ accumulation. Translated fromByulleten' Eksperimental'noi Biologii i Meditsiny, Vol. 129, No. 3, pp. 304–305, March, 2000