Oztekin, EsmaMogulkoc, R.Baltaci, A. K.Tiftik, A. A.2020-03-262020-03-2620060236-5383https://dx.doi.org/10.1556/ABiol.57.2006.3.1https://hdl.handle.net/20.500.12395/20732The aim of this study was to investigate the effect of estradiol and progesterone and melatonin supplementation on TNF-alpha levels in ovariectomized and pinealectomized rats. The study was carried out on 42 adult, Spraque-Dawley strain female rats aged 6 months and weighing 200-250 grams. The rats were divided into 6 groups, each group contained 7 rats. Group 1: Sham-ovariectomized (Sham-Ovx), Group 2: Ovariectomized (Ovx), Group 3: Ovx and estradiol (E) and progesterone (P) supplemented (Ovx+E-P) group, Group 4: Ovx+E-P+Melatonin (M) supplemented group, Group 5: Ovx Pinealectomized (Pnx) group, Group 6: Ovx - Pnx+E-P supplemented group. Serum TNF-alpha levels were determined after 4 weeks application period. Group 6 (Ovx-Pnx+E-P) has the highest serum TNF-alpha compared with other groups while group 2 (ovariectomized), has the lowest levels (P < 0.001). Group 5 was higher than groups 1, 2, 3 and 4 (P < 0.001). The results of the study show that ovariectomy reduces the serum level of TNF-alpha, but estradiol and progesterone application prevents this reduction in ovariectomized rats. However, pinealectomy intensifies the increases in TNF-alpha levels in ovariectomized and estradiol and progesterone supplemented rats, whereas melatonin reduces TNF-alpha levels in ovariectomized rats.en10.1556/ABiol.57.2006.3.1info:eu-repo/semantics/closedAccessovariectomypinealectomyestradiol and progesterone applicationTNF-alpha ratArticle57327528117048691N/AWOS:000241053700001Q3