This study was performed to determine the action mode of oxytocin antagonist. In Study 1, the duration of in vivo action of oxytocin antagonist I (AI) was examined. After infusing AI, oxytocin was given and repeated every hour for 5 hr. Uterine activities were monitored with a polygraph. Study 2 determined the effect of AI on uterine oxytocin receptor number (Rn) and binding affinity (Kd). AI treated rats were sacrificed at 0.5 and 4 hr later for receptor assay. In Study 1, the uterine contractile response to oxytocin was significantly inhibited (p>0.05) compared to controls at five min, 1 and 2 hr after injection of AI. No differences in response were detected compared to controls (p>0.05) at later hours. In Study 2, no differences (p>0.05) between the AI and control animals in either oxytocin receptor number or binding affinity was found. These data suggest that the major mode of AI action is via competitive inhibition at the uterine oxytocin receptor and not by altering receptor number or binding affinity. AI is suggested to have the potential of being a potent and specific tocolytic agent for prevention of preterm labor in human.
Animal ; Female ; Oxytocin/pharmacology ; Oxytocin/metabolism ; Oxytocin/antagonists & inhibitors* ; Rats ; Receptors, Oxytocin/metabolism ; Uterus/physiology ; Uterus/drug effects*

This study was performed to determine the action mode of oxytocin antagonist. In Study 1, the duration of in vivo action of oxytocin antagonist I (AI) was examined. After infusing AI, oxytocin was given and repeated every hour for 5 hr. Uterine activities were monitored with a polygraph. Study 2 determined the effect of AI on uterine oxytocin receptor number (Rn) and binding affinity (Kd). AI treated rats were sacrificed at 0.5 and 4 hr later for receptor assay. In Study 1, the uterine contractile response to oxytocin was significantly inhibited (p>0.05) compared to controls at five min, 1 and 2 hr after injection of AI. No differences in response were detected compared to controls (p>0.05) at later hours. In Study 2, no differences (p>0.05) between the AI and control animals in either oxytocin receptor number or binding affinity was found. These data suggest that the major mode of AI action is via competitive inhibition at the uterine oxytocin receptor and not by altering receptor number or binding affinity. AI is suggested to have the potential of being a potent and specific tocolytic agent for prevention of preterm labor in human.
Animal ; Female ; Oxytocin/pharmacology ; Oxytocin/metabolism ; Oxytocin/antagonists & inhibitors* ; Rats ; Receptors, Oxytocin/metabolism ; Uterus/physiology ; Uterus/drug effects*

To investigate the expression of the subunit p65 of NF-kappaB and inhibitor kappa B alpha (IkappaBalpha) in mouse uterus during peri-implantation, thereby investigating whether transient activation of nuclear factor-kappaB (NF-kappaB) takes place during embryo implantation in mice. Immunohistochemical technique was used to examine the expression and localization of p65 in endometrium or deciduas, and Western blot analysis was employed to detect the levels of IkappaBalpha protein in mouse endometrium or deciduas. P65 protein was detected in stromal cells, epithelial cells of endometrium as well as in myometrium. Staining was predominately seen in the cytoplasm of the cells. Staining intensity for p65 was stronger in the epithelial compartment than the stromal compartment and myometrium. Staining intensity increased slightly during pregnancy, and it reached a high level on pregnancy day 5 and day 8. In contrast to p65, the level of IkappaBalpha protein was lowest on pregnancy day 5 in all groups. Our results suggested that NF-kappaB may regulate embryo implantation by its transient activation in mice.
Decidua/metabolism ; Embryo Implantation/*physiology ; Endometrium/metabolism ; I-kappa B Proteins/*biosynthesis ; NF-kappa B/*biosynthesis ; Time Factors ; Uterus/*metabolism ; Uterus/physiology

Animals ; Cadherins ; metabolism ; Catenins ; metabolism ; Estradiol ; pharmacology ; Estrogen Receptor Modulators ; pharmacology ; Female ; Ovariectomy ; Rats ; Uterus ; drug effects ; metabolism

Female genital tract, which includes oviduct, uterus, and vagina, is critical for female reproduction. In recent years, animal experiments using knockout mice and genetic studies on patients with female genital malformations have contributed substantially to our understanding of the molecular mechanisms in the female genital tract development. Here we review genes that are involved in various stages of female genital tract formation and development.
Animals ; Female ; Genitalia, Female ; growth & development ; metabolism ; Humans ; Mice ; Mice, Knockout ; Uterus ; Vagina

A case of primary yolk sac tumor of endometrium was retrospectively analyzed and relevant literature was systematically reviewed. We found that the primary yolk sac tumor of endometrium showed low incidence rate and was clinically characterized by abnormal vaginal bleeding, intrauterine lesions and significantly elevated alpha-fetoprotein (AFP) level. The final diagnosis should be confirmed by pathological examination. There is no guideline for the treatment of primary yolk sac tumor of endometrium due to its rareness. For now, surgery and chemotherapy are the major therapies and the curative effect is satisfactory in some cases.
Endodermal Sinus Tumor ; diagnosis ; epidemiology ; therapy ; Female ; Humans ; Incidence ; Retrospective Studies ; Uterus ; pathology ; alpha-Fetoproteins ; metabolism

Inositol 1,4,5-trisphosphate receptor 1 (ITPR1) is an important intracellular channel for releasing Ca²⁺. In order to investigate the effects of the ITPR1 overexpression on Ca²⁺ concentration and lipid content in duck uterine epithelial cells and its effects on calcium transport-related genes, the structural domain of ITPR1 gene of duck was cloned into an eukaryotic expression vector and transfected into duck uterine epithelial cells. The overexpression of the ITPR1 gene, the concentration of Ca²⁺, the lipid content, and the expression of other 6 calcium transport-related genes was determined. The results showed that the concentration of Ca²⁺ in uterine epithelial cells was significantly reduced after transfection (P<0.05), the triglyceride content was significantly increased (P<0.01), and the high-density lipoprotein content was significantly decreased (P<0.01). The correlation analysis results showed that the overexpression of the C-terminal half of the ITPR1 gene was significantly positively correlated with the total cholesterol content (P<0.01), which was significantly positively correlated with the low-density lipoprotein content (P<0.05). The overexpression of the N-terminal half of the ITPR1 gene was significantly positively correlated with the triglyceride content (P<0.01), which was significantly negatively correlated with the concentration of Ca²⁺ (P<0.05). RT-qPCR results of 6 calcium transport-related genes showed that the overexpression of the C-terminal half of the ITPR1 gene significantly inhibited the expression of the IP3R2, VDAC2 and CAV1 genes, and the overexpression of the N-terminal half of the ITPR1 gene significantly promoted the expression of the IP3R3 and CACNA2D1 genes. In conclusion, the ITPR1 gene overexpression can promote Ca²⁺ release in duck uterus epithelial cells, promote the synthesis of triglyceride, low-density lipoprotein and cholesterol, and inhibit the production of high-density lipoprotein, and the ITPR1 gene overexpression affected the expression of all 6 calcium transport-related genes.
Animals ; Calcium/metabolism* ; Ducks/genetics* ; Epithelial Cells ; Female ; Inositol ; Inositol 1,4,5-Trisphosphate Receptors ; Lipids ; Uterus

The luminal fluid environment of the female reproductive tract is considered critical for the sperm to undergo a series of molecular events leading to the final acquisition of their fertilizing capacity. It has been shown that the fluid in the female reproductive tract contains high content of HCO3- and it plays an important role in sperm functions including sperm motility, capacitation, hyperactivation and acrosome reaction. This review summarizes the effects of HCO3- on sperm functions occurring in the female reproductive tract and discusses the transport mechanisms involved in mediating uterine HCO3- secretion. New evidence is also presented to show possible cause of female infertility due to defective HCO3- transporting mechanism.
Animals ; Bicarbonates ; metabolism ; Female ; Fertilization ; physiology ; Humans ; Male ; Sperm Capacitation ; physiology ; Sperm-Ovum Interactions ; physiology ; Uterus ; metabolism ; secretion

OBJECTIVETo investigate the effect of cadmium (Cd) on estrogen receptor and to assess its endocrine disrupting action.

METHODSThe estrogen receptor rich supernatant was prepared from the ovariectomized Sprague-Dawley rats. The effects of cadmium on estrogen binding were performed using a sing-dose ligand-binding assay. Extract from uterus were treated with various concentrations of cadmium (0, 10(-3), 10(-5) or 10(-7) mol/L) for various pre-incubation time (0, 30, 60, 90 min) by means of orthogonal experimental design with orthogonal layout of L16(4(5)) (the experiment was repeated for 5 times). In addition to the radioinert competitor, each assay included a zero tube and a DES standard curve for quality control purpose. Data for cadmium and the DES standard curve were plotted as percent [3H]-E2 bound versus log (molar concentration), and the IC50 for cadmium was determined. The RBA for cadmium was calculated by dividing the IC50 of DES in terms of the IC50 of cadmium.

RESULTSCadmium could not block the binding of estradiol to the receptor because hormone binding did not change with increasing cadmium concentration or increasing preincubation time. The results showed that the binding of [3H]-estradiol to uterine cytosols was not significant (P > 0.05). The Bmax (its unit is pmol/mg protein) of various concentrations of cadmium (0, 10(-3), 10(-5) or 10(-7) mol/L) for pre-incubating 0 min is 203.15 +/- 75.16, 203.41 +/- 22.78, 220.82 +/- 45.35, 209.10 +/- 49.66 respectively; The Bmax of them for pre-incubating 30 min is 215.67 +/- 92.97, 139.79 +/- 53.78, 205.27 +/- 23.60, 172.63 +/- 55.09 respectively. The Bmax of them for pre-incubating 60 min is 197.11 +/- 50.68, 203.24 +/- 66.33, 183.92 +/- 31.89, 183.33 +/- 32.70, respectively. The Bmax of them for pre-incubating 90 min is 229.69 +/- 76.88, 175.70 +/- 70.28, 164.26 +/- 24.46, 150.78 +/- 65.97 respectively. Mean IC50 for cadmium is 10(-4) - 10(-3) M. If the affinities of DES binding to estrogen receptors was taken to be 100%, the relative binding affinities of cadmium was 10(-6) - 10(-7). The results indicated that cadmium had only a very poor affinity with estrogen receptor.

CONCLUSIONIn vitro assay cadmium did not have distinct disrupting effect on binding of estradiol to estrogen receptors from rat uterine.

Animals ; Cadmium ; toxicity ; Female ; In Vitro Techniques ; Rats ; Rats, Sprague-Dawley ; Receptors, Estrogen ; drug effects ; metabolism ; Uterus ; drug effects ; metabolism

Dicer is an RNAse III endonuclease that is essential for the biogenesis of microRNAs and small interfering RNAs. These small RNAs transcriptionally and post-transcriptionally regulate mRNA expression through RNA interference mechanisms. Recently, the function of Dicer in female reproduction has begun to be elucidated through the use of knockout mouse models. Several latest studies have indicated that Dicer gene plays a key role in female reproductive processes such as oocyte maturation, early embryonic development and implantation and steroidgenesis. When Dicer expression is decreased in female reproductive tissues or cells, it will cause infertility. In this article, author discuss the role of Dicer gene in female reproductive tract, and advance of Dicer gene study in female reproductive events.
Animals ; Embryonic Development ; genetics ; Female ; Humans ; MicroRNAs ; Ovary ; metabolism ; Ovum ; metabolism ; RNA Interference ; Reproduction ; genetics ; Ribonuclease III ; genetics ; metabolism ; Uterus ; metabolism