Yazar "Celik, Sefa" seçeneğine göre listele
Listeleniyor 1 - 4 / 4
Sayfa Başına Sonuç
Sıralama seçenekleri
Öğe Evaluation of genes involved in prostaglandin action in equine endometrium during estrous cycle and early pregnancy(Elsevier, 2010) Atli, Mehmet O.; Kurar, Ercan; Kayis, Seyit A.; Aslan, Selim; Semacan, Ahmet; Celik, Sefa; Guzeloglu, AydinThe aim was to evaluate expression of genes involved in the biosynthesis of prostaglandins (PTG), Prostaglandin H Synthase-1 (PTGS1) and PTGS2, PGF synthase (PTGFS), and PGE synthase (PTGES), PGF receptor (PTGFR). PGE receptors (PTGER2 and FTGER4), prostaglandin transporter (SLCO2A1) and hydroxyprostaglandin dehydrogenase-15 (HPGD). Endometrial biopsies were obtained from mares on day of ovulation (d0, n = 4), late diestrus (LD, n = 4), early luteolysis (EL n = 4) and after luteolysis (AL n = 4) during the cycle. Stages of the cycle were confirmed by plasma progesterone concentrations measured daily and ultrasound examinations. Biopsies were also taken on days 14 (P14; n = 4), 15 (P15. n = 4), 18 (P18, n = 4) and 22 (P22; n = 4) of pregnancy. Relative mRNA expressions were quantified using real-time RT-PCR. A mixed model was fitted on the normalized data and least significant difference test (alpha = 0.05) was employed. Expression of PTGS1 mRNA was low throughout the estrous cycle and early days of pregnancy, but upregulated on P18 and P22. PTGS2 expression was increased on EL but it was suppressed by pregnancy on P15, P18, and P22. PTGFS expression was upregulated in both cyclic and pregnant mares compared to d0 and its level was the highest on LD. PTGFR expression was transiently increased on LD and EL and was suppressed during early pregnancy. Both PTGES and PTGER2 expressions were increased on LD, El, and early pregnancy, but were decreased after the luteolysis in cyclic mares as they remained high on P18 and P22. PTGER4 expression did not change throughout the cycle and early pregnancy. Levels of HPGD and SLCO2A1 were significantly increased only on P22. In conclusion, PTGS2 expression increases around the time of luteolysis and concurrent upregulation of PTGFS and PTGES indicates that equine endometrium has increased capability of PTG production around the time of luteolysis. However, pregnancy reduces PTGS2 expression, but maintains the high levels of PTGES during early pregnancy along with PTGER2 while PTGFR expression was suppressed. These findings suggest that possible luteotrophic action of PGE(2) is required in early equine pregnancy. PTGS1 is only upregulated later in the early pregnancy suggesting that it is not involved in luteolysis, but could be the main PTGS enzyme at this time during early pregnancy. An increase in HPGD and SLCO2A1 levels on P22 indicates a tight regulation of PTG action by pregnancy. (C) 2010 Elsevier B.V. All rights reserved.Öğe Expression of Epidermal Growth Factor (EGF) and Heparin-Binding EGF (HB-EGF) mRNA in Mare Endometrium(Kafkas Univ, Veteriner Fakultesi Dergisi, 2012) Atli, Mehmet Osman; Guzeloglu, Aydin; Kurar, Ercan; Kayis, Seyit Ali; Aslan, Selim; Semacan, Ahmet; Celik, SefaEGF and HB-EGF play crucial roles in embryonic development and peri-implantation. In this study, aim was to characterize expression profiles of EGF and HB-EGF in mare endometrium during estrous cycle and early pregnancy. Endometrium biopsies were obtained from mares on day of ovulation (d0), late diestrus (LD) and after luteolysis (AL) in the estrus phase. In pregnant groups, biopsies were taken on days 14 (P14), 18 (P18), 22 (P22) and 60 (P60). Relative expression levels of genes were quantified using real-time RT-PCR. A mixed model was fitted on the normalized data and Least Significant Difference (LSD) test was employed to determine significantly different group(s). EGF mRNA expression was up-regulated at LD compared to d0 while HB-EGF expression was not changed throughout the cycle. EGF expression was also increased during early pregnancy with the highest expression level observed on P60. Similarly, HB-EGF mRNA level was increased on P60. Pregnancy induced EGF expression on P14 and P18 compared to LD and AL whereas expression of HB-EGF was only significantly higher on P18 than that of AL. These results indicate that EGF expression is up-regulated during the cycle at late diestrus when P4 is high and is increased by pregnancy. HB-EGF expression is induced later in the pregnancy. In conclusion, EGF and HB-EGF appear to involve in the events that happen in the mare endometrium during peri-implantation period.Öğe Expression of Toll-like Receptors (TLRs) Is Regulated by Early Pregnancy in the Mare Endometrium.(Soc Study Reproduction, 2010) Atli, Mehmet Osman; Kurar, Ercan; Kayis, Seyit A.; Aslan, Selim; Semacan, Ahmet; Celik, Sefa; Guzeloglu, Aydin[Abstract Not Available]Öğe Expressions of Insulin-Like Growth Factor-Binding Proteins (IGFBP) in Mare Endometrium during Estrous Cycle and Early Pregnancy.(Soc Study Reproduction, 2010) Kurar, Ercan; Atli, Mehmet O.; Kayis, Seyit A.; Arslan, Selim; Semacan, Ahmet; Celik, Sefa; Guzeloglu, Aydin[Abstract Not Available]