ABSTRACT
OBJECTIVE: To investigate the effects of heat and noise environments on lipid peroxidation of erythrocyte membrane in pilots. METHOD: Twenty-four pilots and twenty-one ground personnel (control group) served as the subjects. The pilots performed flying in heat and noise environments. Glutathione peroxidase (GSHpx) and malondialdehyde [correction of malondiadehyde] (MDA) levels in erythrocyte membrane were determined before flying (6:00 a.m.), immediately after flying (12:00 a.m.) and 8 hours after flying (8:00 p.m.) respectively with a spectrophotometer. RESULT: Immediately after flying, GSHpx activity in pilot's erythrocyte membrane decreased significantly as compared with that in control group. Immediately after flying and 8 h after flying, MDA contents in pilots increased significantly as compared with that of control group. CONCLUSION: Heat and noise environments might induce increase of lipid peroxidation reaction and decrease of antioxidant ability.
Subject(s)
Erythrocyte Membrane/physiology , Hot Temperature , Lipid Peroxidation/physiology , Noise, Occupational , Adult , Aerospace Medicine , Aviation , Erythrocyte Membrane/enzymology , Erythrocyte Membrane/metabolism , Glutathione Peroxidase/blood , Glutathione Peroxidase/metabolism , Humans , Malondialdehyde/blood , Malondialdehyde/metabolismABSTRACT
Objective. To determine the effect of heat and noise on erythrocyte membrane ATPase activities in pilots during flying. Method. Twenty-four pilots performing bombing for 3 h (45-53 degrees C, 122-97 dB in the cabin) served as the subjects. 21 ground personnel served as control (27 degrees C in the room). Blood samples were taken from both groups before flying (6:00 a.m.), and immediately (12:00 a.m.) and 8 h (8:00 p.m.) after flying. Na(+)-K+ ATPase, and Ca2(+)-Mg2+ ATPase activities in erythrocyte membrane were determined with colorimetry. Result. The Na(+)-K+ ATPase activity in erythrocyte membrane at 6:00 a.m. in pilots was higher than that in control group at the same time (P<0.01). The Ca2(+)-Mg2+ ATPase activities in erythrocyte membrane at 12:00 a.m. and 8:00 p.m. in pilots were significantly higher, compared with those in control group at the same time (P<0.01). Conclusion. The ATPase values obtained in our study were all within normal range, and the daytime variation of both groups are the same. Exposure of human body to heat and noise for long time may be harmful, the higher ATPase activity is, the more catabolism of ATP will be. ATP exhaustion will lead to Ca2+ overload in erythrocyte thus stiffen the red cell membrane.
