Experiments on 72 male Wistar rats using an immunocytochemical method addressed the level of expression of the antiapoptotic factor Bcl-2 in neocortical and hippocampal neurons on exposure to harmful severe (SH) and moderate hypobaric (MHH) hypoxia separately and in combination. SH (180 mmHg) suppressed or had no effect on Bcl-2 expression in neurons in these brain areas. Single episodes of preconditioning (360 mmHg) produced similar effects on Bcl-2 expression as SH. Conversely, repeated preconditioning significantly increased the level of Bcl-2 expression 3–24 h after SH, helping to prevent neuron injury due to SH. MHH itself increased the level of Bcl-2 expression only after multiple (3–6) sessions, while single sessions had no effect on Bcl-2 content. The increases in Bcl-2 expression seen in response to multiple exposures to MHH appear to be important for the formation of the mechanisms increasing the tolerance of cerebral neurons to harmful actions.
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Translated from Morfologiya, Vol. 146, No. 5, pp. 7–13, September–October, 2014.
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Churilova, A.V., Glushchenko, T.S. & Samoilov, M.O. Changes in the Expression of Antiapoptotic Protein Bcl-2 in the Rat Neocortex and Hippocampus in Different Hypobaric Hypoxia Regimes. Neurosci Behav Physi 45, 863–868 (2015). https://doi.org/10.1007/s11055-015-0156-y
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DOI: https://doi.org/10.1007/s11055-015-0156-y