[Identification of specific vasopressin binding sites in cell membranes of the adenohypophysis, liver, kidney and adrenal glands of the rat]. / Vyiavlenie mest spetsificheskogo sviazyvaniia vazopressina na membranakh kletok adenogipofiza, pecheni, pochek i nadpochechnikov krysy.

3H vasopressin specifically binds to the binding sites in liver, kidney and adenohypophysis with Bmax = 11.8 +/- 5.6, 1.7 +/- 0.5 and 4.9 +/- 1.2 pmol/g tissue and Kd = 1.5 +/- 0.5, 0.66 +/- 0.21 and 0.84 +/- 0.21 nM, correspondingly. Specific binding increases in the presence of Mg2+ and Ni2+ and decreases at high temperature (37 degrees). The presence of high affinity binding sites for 3H vasopressin was shown in the rat adrenals, binding was saturable and reversible. Concentration of vasopressin binding sites in adrenals is 6-8 fold less than in adenohypophysis. It is supposed that vasopressin receptors in adrenals may participate in the regulation of corticosteroid secretion.

[The selective role of the nucleus raphe magnus in the mechanisms of analgesia in electrocutaneous pain stimulation, cold stress and the action of morphine]. / Izbiratel'naia rol' bol'shogo iadra shva v mekhanizmakh obezbolivaniia pri élektrokozhnom bolevom razdrazhenii, kholodovom stresse i deistvii morfina.

Inhibition of the analgetic activity of systemic morphine and inescapable foot shock in certain moments of the experiment was shown on rats subjected to electrolytic destruction of nucleus raphe magnus. Cold swim stress increased analgesia as compared to the control animals. It is concluded that this formation of the brain is selectively and dynamically involved in mechanisms of various types of analgesia.

[Interaction of the anxiolytic agent buspirone with serotonin and other synaptic receptors in the human brain]. / Vzaimodeistvie anksioloticheskogo agenta--buspirona s serotoninovymi i drugimi sinapticheskimi retseptorami mozga cheloveka.

Buspirone and Mj 138-05 (up to 0.1 mM) did not displace specifically bound (3H) tryptamine, (3H) strychnine, (3H) flunitrazepam and (3H) imipramine in human cortical and hippocampal membrane preparations. At the same time both compounds displayed similar to serotonin affinity (IC50 in the range of 2-6 microM) for (125I)-LSD specific binding sites in the human cortex and hippocamp. IC50 of serotonin and buspirone and Mj 138-05 for (3H) LSD (2 nM) specific binding sites in the hippocamp was determined as 0.14 microM, 2.3 microM and 6.1 microM, respectively; and for (3H) serotonin specific binding sites in the hippocamp as 0.005 microM, 3.8 microM and 21 microM, respectively. The affinity for human cortex (3H) LSD binding sites was 10-fold lower in case of serotonin and 4-fold lower in case of buspirone and Mj 138-05 than in the hippocamp. However, the affinity for (3H) serotonin binding sites in the cortex was the same as in the hippocamp in case of serotonin and 12-15-fold lower than in the hippocamp in case of buspirone and Mj 138-05. It is concluded that in human brain buspirone and Mj 138-05 interact with micromolar affinity with 5 HT2 and are capable of binding to a subpopulation of 5 HT1 receptors in the hippocamp.

[Role of the locus coeruleus in the mechanism of different types of analgesia]. / Rol' sinego piatna v mekhanizmakh raznykh vidov obezbolivaniia.

The activity of antinociceptive mechanisms during exposure to cold swim stress (CSS), inescapable foot shock (FS) and morphine administration (10 mg/kg) was studied in rats subjected to bilateral lesions of locus coeruleus (LC). It has been shown that under all types of stimulation the latent periods (LP) of nociceptive reactions of paw licking and tail flick were significantly increased, as compared to baseline level, thus suggesting suppression of the pain sensitivity. In rats subjected to CSS and morphine administration significantly shorter LP were revealed in the experimental group, compared to the control, which suggested partial inhibition of antinociceptive mechanisms activity after LC lesion. FS did not cause any differences in the experimental and control groups. It is concluded that LC lesions cannot completely inhibit the antinociceptive mechanisms activated by CSS and morphine injection. In FS monoamine mechanisms of LC do not seem to play an important role in the functioning of antinociceptive mechanisms.

[Analysis of the influence of anxiolytics on the pain reactions of rats compared to the effect of morphine]. / Analiz vliianiia anksiolitikov na bolevye reaktsii u krys v sravnenii s éffektom morfina.

Anxiolytic agents, buspirone and diazepam, increase the paw lick latency of rats in hot plate test, the effect being dose-dependent and exceeding that of morphine. The action of buspirone was not accompanied by ataxic and sedative effects which were observed in rats on diazepam. Buspirone (up to 25 mg/kg) and diazepam (up to 5 mg/kg) neither change the tail flick latency nor potentiate the action of morphine in this test. The effect of buspirone on the paw lick reaction in rats may be related to the inhibition of emotional-motivation component of pain reaction.

[Effect of anxiolytics--buspirone and diazepam--on the prolactin, thyrotropin and cortisol content of the blood in the green monkey]. / Vliianie anksiolitikov--buspirona i diazepama--na soderzhanie prolaktina, tireotropina i kortizola v krovi zelenoi martyshki.

The influence of two anxiolytics--diazepam and buspirone--on prolactin, thyrotrophin and cortisol levels in green monkey (Cercopithecus aethiops) plasma was studied 30 min following i/m injection. Diazepam at 1 mg/kg decreased prolactin and cortisol levels by 30-50% compared to the control animals. Buspirone at 2.5-10 mg/kg induced a 7-10-fold increase in prolactin level but did not change cortisol and thyrotrophin concentration. Buspirone analog--Mj 138-05 at 10 mg/kg produced a 2-3-fold increase in plasma prolactin content in some animals, while at a dose of 5 mg/kg it exerted no detectable effect. Possible neurochemical mechanisms of the effects observed are discussed.

[Effect of buspirone and diazepam on cGMP level in the rat cerebellum]. / Vliianie buspirona i diazepama na soderzhanie tsGMF v mozzhechke krysy.

Diazepam at a dose of 5 and 10 mg/kg significantly decreases (by 50 and 60%, respectively) cGMP content 30 min following intraperitoneal injection to rats. Buspirone, at a dose of 2.5-25 mg/kg produced a nonsignificant (up to 18%) and at a dose of 50 mg/kg a statistically significant (p less than 0.05) 30% decrease in cerebellum cGMP content. Taking into account the identical anxiolytic effects of diazepam and buspirone, it is suggested that pharmacological effects of buspirone are not linked to the activation of GABA-ergic system.

[Detection of an endogenous inhibitor of benzodiazepine receptor binding]. / Vyiavlenie éndogennogo ingibitora retseptornogo sviazyvaniia benzodiazepinov.

An original one-stage method for isolating from brain tissue of a water-soluble fraction containing an inhibitor of benzodiazepine specific binding is suggested and the properties of the inhibitor are described. The inhibitor is a thermostable compound with a molecular mass of 2000-10000 dalton. It inhibits diazepam binding depending on the concentration. The IC50 for diazepam binding is approximately ten-fold less than the inhibitor concentration in the brain tissue. The inhibitor is distributed heterogeneously in the rat brain (the maximal content in the cerebellum and cortex) and bovine brain (the maximal content in the thalamus and caudate nucleus).

[Fenibut binding with bicuculline-insensitive GABA receptors in the rat brain]. / O sviazyvanii fenibuta s bikukullinnechuvstvitel'nymi retseptorami GAMK v mozge krys.

(+/-) Fenibut beta-phenyl-GABA) was not able to displace 3H-GABA in Na+ independent GABA binding (IC50 greater than 250 microM). Nevertheless, (+/-) fenibut and (+/-) baclofen effectively displaced 3H-GABA in Ca2+ dependent GABA binding in the presence of 50 microM (+) bicuculline. (+/-) Fenibut was less potent in this respect. It is suggested that fenibut may act via bicuculline-insensitive GABA receptors.

[Physicochemical heterogeneity of the GABA receptors and the detection of the differences in their structural relation with benzodiazepine receptors]. / Fiziko-khimicheskaia geterogennost' GAMK-retseptorov i vyiavlenie razlichii v strukturnoi sviazi s benzodiazepinovymi retseptorami.

The existence of two subpopulations of GABA-receptors was shown by cation-exchange chromatography and isoelectrofocusing methods. One of these populations was purified together with the benzodiazepine receptors. Isoelectric points determined for the two GABA-receptor subpopulations were 4.6 - 5.3 and 5.6 - 5.9. Isoelectric points for the benzodiazepine receptor were 5.6 - 6.1.

[Immunochemical study of the water-soluble lens proteins in the embryo of Xenopus laevis with the mutation of periodic albinism]. / Immunokhimicheskoe izuchenie vodorastvorimykh belkov khrustalika u zarodysha Xenopus laevis s mutatsiei periodicheskogo al'binizma.

The crystallins of ap mutants of Xenopus laevis have been studied in comparison with those of normal embryos and adults using the complex of immunochemical methods (immunoelectrophoresis, immunodiffusion, immunoadsorption, immunofluorescence, isoelectrofocusing with immunoidentification). The analysis was carried out with antisera to electrophoretic fractions of the mutant lens. 11 organ-specific antigens were found in the lens of both the normal and mutant animals. These proteins are heterogenous by electrophoretic mobility, isoelectrical point, antigenic and species specificity. Each class of crystallins contains antigens which are specific: a) for amphibians only, b) for lower vertebrates, c) for vertebrates in general. No qualitative differences were found between crystallins of the normal and mutant animals. Immunofluorescence analysis has shown that crystalins appear in the normal and mutant embryos practically at the same time. No significant differences in the appearance of specific immunofluorescence between the normal and mutant embryos were found (with various antisera). gamma-crystallins and, perhaps, a part of the primary lens fibers. Alpha-crystallins appear later. gamma-crystallins are first identified the synthesis of which manifests itself at the advanced developmental stages. The quantitative predominance of some beta--gamma-crystallins in the mutant lens detected by us (electrophoresis, isoelectrofocusing) is not related to their earlier synthesis in the embryogenesis.