Influence of exposure in hyperbaric chambers on selected parametersof oxidative stress in professional divers.

PURPOSE: This study evaluated the influence of hyperbaric exposure chambers on selected parameters of oxidative stress in divers' blood.

METHODS

25 healthy men (non-smoking experienced divers) ages 18-40 took part in the experiment. Subjects were exposed to hyperbaric conditions similar to those at 30 meters of depth while diving. A control group consisted of 20 healthy men who have never dived or been exposed to hyperbaric conditions. Blood was drawn from the cubital vein after overnight fasting. Superoxide dismutase (SOD-1) activity and malondialdehyde (MDA) concentration were marked in red blood cells (RBCs), carbonyl group concentration marked in serum proteins, and nitrate/nitrite concentrations were estimated in plasma.

RESULTS

Statistically significant differences were found between the divers and the control group in MDA concentration in erythrocytes and carbonyl group concentration in serum proteins. Nitrite/nitrate concentrations in plasma plus SOD-1 activity in RBCs decreased significantly in the diver group compared with the control group. After hyperbaric exposure MDA concentration in erythrocytes increased considerably in the test group and a significant increase in SOD-1 activity was observed. A significant increase of nitrite/nitrate concentration was noted in plasma as well as an increase in the carbonyl group in serum proteins.

CONCLUSION

Considerably weak enzymatic antioxidative defense was observed in the RBCs of individuals exposed to hyperbaric pressures versus those in normobary. This issue indicates that a diver's system has a larger susceptibility for negative effects from oxidative stress. The results also indicate that hyperbaric conditions can intensify reactions via free radicals.