N.A. Loginova Ph.D. (Biol.), Senior Research Scientist, Laboratory of Functional Neurocytology, Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow E-mail: nadinvnd@yandex.ru N.V. Panov Assistant, Laboratory of Functional Neurocytology, Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow E-mail: nikolay.panov1966@yandex.ru A.A. Potekhina (Prokuratova) Junior Research Scientist, Laboratory of Functional Neurocytology, Institute of Higher Nervous Activity and Neurphysiology of RAS, Moscow E-mail: unsinn2@yandex.ru N.S. Kositsyn Dr.Sc. (Biol.), Professor, Chief Research Scientist, Honored Scientist of Russian Federation, Laboratory of Functional Neurocytology, Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow E-mail: nikolay.kositzyn@mail.ru M.M. Svinov Ph.D. (Biol.), Head of Laboratory, of Functional Neurocytology, Institute of Higher Nervous Activity and Neurophysiology of RAS, Moscow E-mail: svinov@ihna.ru

In present study we have investigated the anxiety of rats after cerebral ischemia and the number of neuronal gap junctions in core, penumbra and intact zone of neocortex, where we produced ischemia by method of photochemical thrombosis. We used four groups of rats: sham rats (n=13), sham rats with i.v. injection of carbenoxolone in dose 1mg/kg (n=15), rats after cerebral ischemia (n=24) and rats with i.v. injection of carbenoxolone in dose 1mg/kg , 30 minutes after cerebral ischemia (n=25). A day before cerebral ischemia all rats were tested in open field, second test were carried out on 4th day after ischemia and on 6th day after ischemia all rats were tested in elevated plus maze. On 8th day all rats were taken for immunohistochemical analysis and we have investigated the number of neuronal gap junctions in intact zone, penumbra and core, staining their brains using immunostaining to connexin-36. The level of anxiety was increased in sham rats with carbenoxolone injection and in rats with cerebral ischemia. The number of neuronal gap junctions were decreased compared with sham group (p<0.05) in both groups. The opposite effect we have observed after carbenoxolone injection to experimental ischemic rats. Their behavior was similar to sham rats, as well as the number of gap junctions. Carbenoxolone injection to experimental ischemic rats reduced the level of anxiety and increased the number of neuronal gap junctions. We suppose that changes in behavior and in number of gap junctions may be caused by indirect impact of carbenoxolone on glucocorticoid system. The reported study was supposed by RFBR, research project No. 14-04-32121 mol_a

 

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