ABSTRACT
Objective: implantation failure is an obstacle in assisted reproduction techniques [ART]. Calcitonin is a molecules involved in uterine receptivity and embryo implantation. Melatonin can promote embryo quality and improve implantation. This study examines the effect of pretreatment of blastocysts with melatonin and calcitonin on heparin binding-epidermal growth factor [HB-EGF] expression in murine endometrium
Materials and Methods: in this experimental study, we collected 2-cell embryos from the oviducts of 1.5 day pregnant NMRI mice. Embryos were cultured to the blastocyst in G[TM] medium with or without 10[-9] M melatonin. Pregnant and pseudo-pregnant mice received intraperitoneal [IP] injections of 2 IU calcitonin. After 24 hours, we transferred the cultured blastocysts into the uteri of pseudo-pregnant mice. Two days later, implantation sites were counted and we assessed the levels of HB-EGF mRNA and protein in the uteri of naturally pregnant and pseudo-pregnant mice by quantitative real-time polymerase chain reaction [qRT-PCR] and Western blot. Statistical analysis was performed with one-way ANOVA followed by the Tukey post hoc test. P<0.05 was considered statistically significant
Results: melatonin pretreatment of blastocysts along with calcitonin administration significantly increased HB-EGF mRNA and protein [P<0.001] in the endometrium of pseudo-pregnant mice. Administration of calcitonin in naturally pregnant mice significantly increased HB-EGF mRNA and protein levels [P<0.001]. Compared with the control group [2.6 +/- 0.5], the average number of implantation sites in the melatonin group [4.6 +/- 0.5, P<0.05] and calcitonin group [7 +/- 1, P<0.001] significantly increased. There was a significant increase in implantation sites in the combined melatonin and calcitonin group [8.6 +/- 0.5, P<0.001]. Calcitonin significantly enhanced calcitonin receptor mRNA [P<0.001] and protein [P<0.05] in the uteri of naturally pregnant and pseudo-pregnant mice
Conclusion: melatonin pretreated blastocysts along with calcitonin increased HB-EGF expression in the uteri of pseudopregnant mice. Calcitonin administration upregulated HB-EGF in uteri of naturally pregnant mice
ABSTRACT
Nowadays nitric oxide [NO] is an important signaling molecule which acts as a regulator of many physiological processes in many tissues including epithelial cell of gastrointestinal tract. In this study, we investigated the effects of L-Argentine as a NO precursor and L-NAME as a NO inhibitor on epithelial cell number and height of jejuna epithelium in rats. In this experimental study, 40 adult female rats with 8 weeks age and 200-250 g weight were divided into 5 groups, containing 8 rats in each group. Except the control group, the other groups received normal saline [2 mL/kg], L-Argentine [200 mg/kg], L-NAME [20 mg/kg] and a mixture of 2 substances for L-Argentine and L-NAME group intraperitonealy for 3 days. Two weeks later, jejunum was expelled out and after fixation and tissue processing, the sections were stained with Hematoxylin and Eosin method and the changes were assessed. Cell number and height was evaluated using Image Tools III Microsoft software. Statistical analysis was made by One-Way ANOVA followed by Turkey post hoc test to evaluate the statistical significance between different groups. A value of p<0.05 was considered statistically significant. There was a significant increase in the cell number and height of jejuna epithelium in L-Argentine group [p<0.05]. Whereas no significant difference was observed between L-NAME, L-Arginine+L-NAME, normal saline and control groups. The results demonstrated that L-Argentine can result in proliferation of jejuna epithelial cells whereas L-NAME has no effect on these cells