Effects of increasing ratio of progesterone in estrogen/progesterone combination on total oxidant/antioxidant status in rat uterus and plasma

Purpose The relationship between increasing ratio of progesterone in estrogen/progesterone combination and oxidative stress (OS) was investigated. Methods Thirty non-pregnant Wistar Albino female rats were divided into five groups and bilaterally ovariectomized (Ovx) except sham group. Groups Sham + 0.3 cc seaseme oil, Ovx + 0.3 cc seaseme oil, Ovx + estradiol propionate (E2) (1 μg/kg), Ovx + E2 + medroxyprogesterone acetate (MPA) 1 mg/kg, Ovx + E2 + MPA 20 mg/kg. Hormones were applied for three consecutive days after 28 days of ovariectomy. Their uteri and blood samples were collected and nitric oxide (NO), malondialdehyde (MDA), total oxidative status (TOS) and total antioxidant capacity (TAC) levels were determined. Results E2 + MPA1 treatment decreased NO, MDA and TOS levels and increased TAC levels in uterus. Plasma NO levels elevated in all groups and MDA production increased due to E2 treatment when compared to ovariectomy. E2 + MPA20 treatment increased TOS levels, while TAC levels decreased when compared to ovariectomy in plasma. Conclusions Using E2 plus low dose progesterone may prevent pathologies resourced of OS.