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

In the present study we have investigated the distribution of neuronal gap junctions in the rat brain after focal ischemia induced by photochemical thrombosis. We used adult male Wistar rats (m = 300 - 350 g). Cerebral ischemia was produced by photochemical clotting in the somatosensory cortex of the rat brain. The luminous flux power was 1,2mW/mm2 for creating an ischemic focus in surface layers and 2,8 mW/mm2 for creating an ischemic focus in all cortical layers. A day after the thrombosis the brains were used for histological research. Brain slices were stained by immunohistochemical method against Cx36. The average number of neuronal gap junction per one cell was calculated at the brain slices. It was obtained that average number of neuronal gap junctions increased in core at weak ischemia, and in core and penumbra at middle ischemia. Thus, we assume that the strengthening of intercellular communication due to increase of gap junctions may contribute positively to neuroprotection. The reported study was supported by RFBR, research project No. 14-04-32121 mol_a.

 

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