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INFLUENCE OF LONG-TERM EXPOSURE TO STATIC, HIGH VOLTAGE ELECTRIC FIELD ON ANTIOXIDANT ACTIVITY IN RATS

(1) Chair and Clinic of Internal Diseases, Angiology and Physical Medicine, Silesian Medical University, PL-41902, Bytom, Poland; (2) Chair, Department of Biochemistry, Silesian Medical University, PL-41808, Zabrze, Poland; Institute of Power System and Control, Silesian University of Technology, PL-41100, Gliwice, Poland
01/2005;

ABSTRACT In this study the influence of long-term, whole-body exposure to strong, static electric field generated usually near direct current high voltage transmission lines on activity of some antioxidant enzymes in liver homogenats of rats was investigated. Experimental material consisted of 96 male Wistar albino rats aged 8 weeks, weighting 180-200 g. During the whole experiment all animals were placed in identical environmental conditions under a 12 h light-dark cycle with free access to standard laboratory pellet food and tap water. All animals were randomly divided into 3 groups (32 animals each). The rats from two experimental groups were exposed for 56 consecutive days (8 hours daily) to static electric field with electric field intensity values of 16 kV/m and 35 kV/m respectively, in a specially designed experimental system. The control animals were subjected to a sham-exposure in the same experimental system, during which no electric field was generated between electrodes. At 14 th , 28 th and 56 th day of exposure cycle and then in 28 th day after the end of exposure cycle a part of animals from all groups (8 rats at a same time) was exsanguinated in Morbital narcosis. Then in liver homogenats prepared from obtained liver samples the activity of some antioxidant enzymes as catalase, glutathione peroxidase and superoxide dismutase was determined with use of spectrophotometric methods as well as the concentration of malone dialdehyde (marker of intensity of oxidative processes in tissues) was estimated. As a result of repeated exposures a trascient statistically significant decrease in activity of catalase in second experimental group at 28 th day of exposure cycle, a significant increase in activity of glutathione peroxidase in first experimental group at 56 th day of exposure cycle and in second experimental group at 14 th and 28 th day of exposure cycle, a significant decrease in superoxide dysmutase activity in first experimental group at 14 th day of exposure cycle and in second experimental group at 28 th day of exposure cycle as well as a significant decrease in malone dialdehyde concentration in homogentas of liver tissue in second experimental group at 28 th day of exposure cycle and in both groups of electric field-exposed rats at 28 th day after the end of exposure cycle as compared to control rats was observed. On the basis of obtained results it was concluded that strong static electric fields with parameters generated usually nearby high voltage direct current transmission lines does not cause any persistent effect on antioxidant reactions in living organism. These data indicate that proper construction of high voltage direct current transmission lines enables to avoid serious health hazards for human population related to disturbances of antioxidant processes in living organisms.

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