Open AccessHydrogen peroxide metabolism in alveolar macrophages after exposure to hypoxia and heat
Author(s) -
Lobanova Em,
Tahanovich Ad
Publication year - 2006
Publication title -
physiological research
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.647
H-Index - 70
eISSN - 1802-9973
pISSN - 0862-8408
DOI - 10.33549/physiolres.930863
Subject(s) - chemistry , catalase , tbars , hydrogen peroxide , hypoxia (environmental) , oxygen , incubation , thiobarbituric acid , nitrite , superoxide dismutase , superoxide , antioxidant , reactive oxygen species , biochemistry , glutathione peroxidase , glutathione , lactate dehydrogenase , enzyme , lipid peroxidation , organic chemistry , nitrate
High temperature can change the effects of intra- and intercellular regulators and therefore modify the cellular response to hypoxia. We investigated H(2)O(2) production by alveolar macrophages, isolated from adult male rats, which were incubated under conditions of oxygen deficiency and high temperature (experiment in vitro). The incubation of these cells for 2 hours at 10 % or 5 % oxygen led only to slight fluctuations in the H(2)O(2) level, while the rise of temperature from 37 degrees C up to 42 degrees C significantly increased its generation. Level of thiobarbituric acid-reactive substances (TBARS) underwent similar changes. Under these conditions the accumulation of H(2)O(2) was found to be caused mainly by its decreased cleavage rather than its enhanced production. This is indicated by decreased catalase and glutathione peroxidase activity together with a parallel absence of significant changes in superoxide dismutase (SOD) activity. Slight fluctuation of reduced glutathione level and the pronounced increase of glucose-6-phosphate dehydrogenase (G6PD) activity were detected. Strong (5 %) but not moderate (10 %) lack of oxygen led to a sharp increase in formation of cellular nitrite ions by alveolar macrophages. In general, our data showed that high temperature did not lead to any qualitative shifts of defined hypoxia-derived changes in oxidant/antioxidant balance in alveolar macrophages, but promoted sensitivity of cells to oxygen shortage.