This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Similar articles in this journal Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via Google Scholar Google Scholar Articles by Shimamura, K. Articles by Kato, H. Search for Related Content PubMed Articles by Shimamura, K. Articles by Kato, H.

Changes in lipid peroxide and antioxidant enzyme activities in corpora lutea during pseudopregnancy in rats

This study investigated the involvement of lipid peroxidation and antioxidant enzymes in the regulation of luteal function in pseudopregnant rats. The activities of superoxide dismutase (SOD), a specific scavenger of superoxide radicals, and glutathione peroxidase, a scavenger of hydrogen peroxide, and lipid peroxide concentrations were measured in the corpus luteum on days 1, 3, 5, 7, 9, 11 and 13 of pseudopregnancy. The activity of SOD in the corpus luteum gradually increased until day 9 of pseudopregnancy and decreased thereafter, in a similar manner to serum progesterone concentration. Glutathione peroxidase activity significantly increased from day 1 to day 3 and remained high until day 11 of pseudopregnancy. The concentrations of lipid peroxides in the corpus luteum increased from day 3 to day 13 of pseudopregnancy. The involvement of prostaglandin F₂ (PGF₂) in the production of lipid peroxides in regression of the corpus luteum was investigated by administering PGF₂ (3 mg kg^–1, s.c.) or saline on days 7, 9 and 12 of pseudopregnancy. Each group of rats was autopsied 2 h later, and SOD activity, glutathione peroxidase activity and the concentration of lipid peroxides in the corpus luteum were determined. PGF₂ significantly increased lipid peroxide concentrations in the corpus luteum on days 7, 9 and 12 of pseudopregnancy (approximately twofold increases on days 7 and 9, and a fivefold increase on day 12, compared with the control that received saline). The activity of SOD in the corpus luteum was significantly increased by PGF₂ on days 7 and 9, but not on day 12, of pseudopregnancy. PGF₂ did not cause any significant changes in glutathione peroxidase activity in the corpus luteum on days 7, 9 and 12 of pseudopregnancy. It is concluded that lipid peroxides play an important role in regulating luteal function in pseudopregnant rats.