Reproductive aging results in a reconfigured ovarian antioxidant defense profile in rats

Objective: To test our hypothesis that reproductive aging changes the ovarian oxidative stress defense profile, in response to prostaglandin F2α (PGF2α) during corpus luteum regression, because how a cell or an organ handles reactive oxygen intermediates may be dependent on the biological age of the organism. Design: Animal experimentation using rat model of corpus luteum regression. Setting: University reproductive biology laboratory. Animal(s): Control (26-day-old) and 8- to 9-month-old (reproductive aging) rats. Intervention(s): Corpus luteum formation was induced in control and 8- to 9-month-old (reproductive aging) rats with pregnant mare serum gonadotropin followed by human chorionic gonadotropin. Regression was then initiated with PGF2α. Main Outcome Measure(s): Vitamin E, glutathione reductase, glutathione peroxidase, catalase, and thiobarbituric acid-reacting substances were measured. Result(s): Ovaries from reproductive aging rats, compared with the control (26-day-old) group, had elevated vitamin E levels at 0, 2, and 24 hours after PGF2α. At 2 and 24 hours after PGF2α, the aging ovaries had lower glutathione reductase levels. Conclusion(s): These data suggest that the reproductive aging ovary has a transformed oxidative stress defense profile and that this may account for some of the physiological changes found in reproductive aging.