Changes in catalase activity and hydrogen peroxide level in rat ovary during estrous cycle and induction of catalase in rat ovary by estradiol-17 beta.

Catalase activity in the whole ovary homogenate and hydrogen peroxide level in the differentially centrifuged fractions of the ovary homogenate during each stage of estrous cycle were measured. The highest catalase activity was observed in the metestrous which declined in the estrous and proestrous and was lowest in the diestrous. An inverse relationship was found between catalase activity and hydrogen peroxide production. Treatment of immature (28-29 days old) female rats with estradiol-17 beta (5 micrograms in 0.2 ml oil/animal/day for consecutive 3 days, s.c.) increased the ovarian catalase activity. The findings indicate that the free radical-scavanger system may have functional role in the ovary.