Effect of Estrogen, Progesterone, LH, and FSH on Oxidant and Antioxidant Parameters in Rat Uterine Tissue

Background: To attain whether the effects of low and high doses of estrogen, progesterone, luteinizing hormone (LH), and follicle stimulating hormone (FSH) in acute and chronic administration were related to oxidant and antioxidant parameters in rat uterine tissue as well as cyclooxygenase-1 (COX-1) activity. Materials and Methods: Acute and chronic administration of estrogen (1 and 5 mg/ kg), progesterone (1 and 5 mg/kg), LH (20 U/kg), and FSH (250 U/kg). A combination of mifepristone (50 mg/kg) with progesterone (5 mg/kg) and FSH (250 U/kg); and yohimbine (10 mg/kg) with estrogen (5 mg/kg) and LH (20 U/kg). Measurement total glutathione, nitric oxide levels and malondialdehyde, myeloperoxidase and COX-1 activities. Results: Acute and chronic administration of progesterone 5 mg/kg and FSH 250 U/kg; and chronic administration of estrogen 1 mg/kg decreased antioxidants and increased oxidants. Combined administration of yohimbine with estrogen and LH showed the effect on these parameters. Conclusion: While LH had a protective effect, low chronic dose estrogen caused oxidative stress. Because low doses could not stimulate alpha-2 receptors and it inhibited LH, an antioxidant hormone. High doses of estrogen that stimulated alpha-2 receptors showed a stable trend in oxidant and antioxidant levels in both acute and chronic administration. High doses of progesterone had an oxidant effect when it stimulated its own receptor in acute and chronic administration. In low acute and chronic doses, though progesterone could not stimulate its receptors but could inhibit FSH, it showed no effect. The oxidant effects of progesterone and FSH were blocked by mifepristone.