The protective role of a hypothalamic proline-rich peptide during acute intoxication of rats by carbon dioxide in combination with oxygen starvation

Abstract

We measured the contents of NADPH oxidases (Nox) in the membranes of erythrocytes, spleen cells, bone marrow cells, nuclei from spleen cells, and blood serum of rats that were subjected to action of carbon dioxide under conditions of oxygen starvation. We found that some increase in Nox content during intoxication with CO2 correlates with an increase in the superoxide-producing activity of Nox. Intraperitoneal administration of the synthetic analogue of the proline-rich peptide, which was previously extracted from neurosecretory granules of the hypothalamus and is referred to as galarmin, 1 hour before the treatment with CO2 resulted in a further increase in the content and superoxide-producing activity of Nox. The methemoglobin-reducing activity of Nox, which was decreased due to CO2 intoxication, increased in the presence of galarmin. We also found that considerable changes in the activities of superoxide dismutase and catalase in the cytosol of erythrocytes and the cells of rat spleen, which were induced by CO2, were reverted by galarmin, which returned these activities almost to their norm. The data we obtained suggest that galarmin may have a protective effect during CO2 intoxication under conditions of oxygen starvation.