title: Effect of temperature on production of hypochlorous acid by stimulated human neutrophils.
abstract: Under natural conditions or because of therapy with heat or cold, neutrophils may function at times in the human body at temperatures other than 37 degrees C. Therefore, we evaluated the effects of temperature on several functions of these cells. Phagocytosis and superoxide production by stimulated neutrophils were optimal at 37 degrees C and attained at least 70% of this peak value at 42 degrees C. In contrast, production of hypochlorous acid (as measured by an assay using the chlorination of taurine) by stimulated neutrophils was optimal at temperatures less than 37 degrees C and attained only 13% to 15% of this peak value at 42 degrees C. During a 2-hour incubation, the major suppressive effects of the higher temperature occurred during the second hour. This result was not explainable by factors related to the hypochlorous acid assay system or by loss of cell viability or myeloperoxidase activity in the cell supernatants, but rather appeared to be caused by reduced generation of hydrogen peroxide at the higher temperatures. Because the extracellular release of a strong oxidant such as hypochlorous acid might result in significant tissue injury, suppression of the release of this oxidant by elevated temperatures may explain why the application of local heat sometimes benefits certain inflammatory conditions.
mesh_terms: D002470:Cell Survival; D006735:Horseradish Peroxidase / Q000097:blood; D006801:Humans; D006861:Hydrogen Peroxide / Q000378:metabolism; D006997:Hypochlorous Acid / Q000378:metabolism*; D066298:In Vitro Techniques; D007249:Inflammation / Q000378:metabolism; D009504:Neutrophils / Q000378:metabolism*; D009195:Peroxidase / Q000097:blood; D010587:Phagocytosis; D013481:Superoxides / Q000378:metabolism; D013654:Taurine / Q000378:metabolism; D013696:Temperature
chemical_list: D013481:Superoxides; D013654:Taurine; D006997:Hypochlorous Acid; D006861:Hydrogen Peroxide; D006735:Horseradish Peroxidase; D009195:Peroxidase