Use of statins and risks of ovarian, uterine, and cervical diseases: a cohort study in the UK Biobank.

PURPOSE: To examine the associations between use of statins and risks of various ovarian, uterine, and cervical diseases, including ovarian cancer, endometrial cancer, cervical cancer, ovarian cyst, polycystic ovarian syndrome, endometriosis, endometrial hyperplasia, endometrial polyp, and cervical polyp. METHODS: We conducted a cohort study among female participants in the UK Biobank. Information on the use of statins was collected through verbal interview. Outcome information was obtained by linking to national cancer registry data and hospital inpatient data. We used Cox proportional hazards regression to examine the associations. RESULTS: A total of 180,855 female participants (18,403 statin users and 162,452 non-users) were included. Use of statins was significantly associated with increased risks of cervical cancer (adjusted hazard ratio (HR), 1.55; 95% confidence interval (95% CI), 1.05-2.30) and polycystic ovarian syndrome (adjusted HR, 4.39; 95% CI, 1.68-11.49). However, we observed no significant association between use of statins and risk of ovarian cancer, endometrial cancer, ovarian cyst, endometriosis, endometrial hyperplasia, endometrial polyp, or cervical polyp. CONCLUSION: Our findings suggest that use of statins is associated with increased risks of cervical cancer and polycystic ovarian syndrome, but is not associated with increased or decreased risk of ovarian cancer, endometrial cancer, ovarian cyst, endometriosis, endometrial polyp, or cervical polyp.

TT-10 may elevate YAP and repair mouse uterine damage resulting from the inhibition effect of ibuprofen on COX2-PGE2 and YAP.

Ibuprofen (IBU) is an emerging environmental contaminant that, in high doses, can damage reproductive organs in humans and other mammals. Recently, its effects on the uterus have been investigated. It is known that the COX2-PGE2 pathway and Yes-associated protein (YAP) are involved in female reproductive organ development and form a COX2-PGE2-EP2-Gas-ß-catenin-YAP-COX2 positive feedback loop, in addition, TT-10, a pharmacological product, has been found to increase YAP. In this study, IBU was orally administrated to female mice for 7 d at doses of 0, 50, 100, and 200 mg/kg·bw/day (control, low, medium, and high doses, respectively). In addition, 0, 50, 100, and 200 µmol/L IBU was added in vitro to cultured uterine cells for 7 d at control, low, medium, and high doses, respectively; then, 0, 5, 10, and 20 µmol/L TT-10 were given to the in vitro uterine culture containing 100 µmol/L IBU to observe the effect of YAP activation. The results showed that medium and high doses of IBU inhibited the COX2-PGE2 pathway, decreasing YAP and increasing pYAP, leading to reduced circPVT1, elevated miR-149, and increased apoptosis, ultimately damaging the uterus. Conversely, 10 µmol/L TT-10 maximally enhanced YAP, which regulated COX2-PGE2 pathway activation, increased circPVT1, and decreased miR-149, and promoted cell proliferation, preventing uterine damage. This suggests that IBU may cause uterine damage by inhibiting the COX2-PGE2 pathway and YAP, and that appropriate doses of TT-10 may repair this damage by elevating YAP and stimulating COX2 via the feedback loop.

Intrauterine Adhesions After Chlamydia Infection With a Levonorgestrel-Releasing Intrauterine Device in Place.

BACKGROUND: Little is known about the long-term reproductive effects of pelvic infection when a levonorgestrel-releasing intrauterine device (LNG-IUD) is in situ. Society guidelines do not recommend removing an LNG-IUD during pelvic infection. CASE: A 37-year-old woman presented with primary infertility, and the only contributing factor was intrauterine adhesions in the shape of an IUD. She was known to previously have an LNG-IUD and was treated for asymptomatic chlamydia infection while the IUD was in place. After lysis of adhesions, she successfully conceived spontaneously. CONCLUSION: Data on long-term reproductive effects of pelvic infection with an LNG-IUD in situ are not available, and there may be consequences affecting the intrauterine milieu requiring further studies and potential counseling.

Protective effect of Coenzyme Q10 on oxidative ovarian and uterine damage induced by methotrexate in rats.

Methotrexate (MTX) has toxic effects on the uterus and ovaries via oxidative stress. Coenzyme Q10 (CoQ10) is an important component in electron transport in the mitochondria and an antioxidant in cellular metabolism through the inhibition of lipid peroxidation. The aim of this study was to investigate the preventive effects of CoQ10 on MTX-induced utero-ovarian damage and oxidative stress in rats.In this experimental study, 30 albino Wistar female rats were divided randomly into three groups. Once a day for a month, 10 mg/kg of CoQ10 was orally administered to the rats in the MTX+CoQ10 group, while the same volume of olive oil was administered orally to the other two groups. One hour thereafter, 20 mg/kg of MTX was injected intraperitoneally into the rats in the MTX and MTX+CoQ10 groups; the remaining group was the control. At the end of the month, biochemical and histopathologic examinations were performed on the extracted uteri and ovaries. In the uterine ovarian tissues of the animals in the MTX group, there was an increase in oxidative stress mediators and a decrease in antioxidant and anti-inflammatory mediators, but these trends were reversed in the MTX+CoQ10 group, demonstrating the antioxidant effects of CoQ10. MTX leads to oxidative stress-related ovarian and uterine injury, and CoQ10 may be useful for protecting ovarian and uterine tissue from such injury.

Effect of Gloriosa superba linn (EEGS) on mPT and monosodium glutamate-induced proliferative disorder using rat model.

ETHNOPHARMACOLOGICAL RELEVANCE: Hyperplasia, Tumors and cancers are various forms of proliferative disorders affecting humans. Surgery is the main treatment approach while other options are also associated with adverse effects. There is therefore a need for the development of better alternative therapy that is cost effective and readily available with little or no adverse effect. Some bioactive agents in medicinal plants exhibit their anti-proliferative potential by induction of mitochondrial permeability transition pore (mPT) opening. Gloriosa superba, a medicinal plant, is folklorically used in the treatment of tumors and cancers. AIM OF THE STUDY: This study therefore aimed at investigating the effect of ethanol leaf extract of Gloriosa superba (EEGS) on mPT and monosodium glutamate-induced proliferative disorder in some specific tissues using rat model. MATERIALS AND METHODS: Isolated rat liver mitochondria were exposed to different concentrations (10, 30, 50, 70 and 90 µg/ml) of EEGS. The mPT pore opening, cytochrome c release, mitochondrial ATPase activity and lipid peroxidation were assessed spectrophotometrically. Caspases 9 and 3 activities were carried out using ELISA technique. Histological assessment of the liver, prostate and uterus of normal and monosodium glutamate (MSG)-treated rats were carried out. RESULTS: The results showed significant induction of mPT pore opening, release of cytochrome c, enhancement of mitochondrial ATPase activity, inhibition of lipid peroxidation and activation of caspases 9 and 3 activities by EEGS. The histological assessment revealed the presence of MSG-induced hepato-cellular damage, benign prostate hyperplasia and uterine hyperplasia which were ameliorated by EEGS co-administration. CONCLUSIONS: These findings suggest that EEGS contains putative agents that can induce apoptosis via induction of mPT pore opening and as well protect against MSG-induced hepato-cellular damage and proliferative disorder in prostate and uterus.

WJ­MSCs intervention may relieve intrauterine adhesions in female rats via TGF­β1­mediated Rho/ROCK signaling inhibition.

Estrogen is a commonly used hormone in the adjuvant treatment of intrauterine adhesion (IUA), which can promote endometrial growth. Stem cell transplantation has also been reported to promote endometrial regeneration in IUA due to its potential differentiative capacity. Human Wharton's jelly mesenchymal stem cells (WJ­MSCs) are isolated from the umbilical cord, possess strong self­renewal and proliferative abilities, and are hypo­immunogenic and non­tumorigenic. Therefore, the present study aimed to investigate the therapeutic effects and underlying mechanism of WJ­MSCs transplantation with estrogen treatment, separately or as a combined therapy, on IUA. The IUA model was established using the ethanol damage method. A total of 50 Sprague­Dawley female rats were randomly divided into the control, IUA model, WJ­MSCs treatment, estrogen treatment and WJ­MSCs+ estrogen treatment groups (n=10/group). WJ­MSCs were injected three times at 5­day intervals. IUA rats in the estrogen group received 0.2 mg/kg estrogen through intragastric administration, once every 2 days for 8 weeks. Morphological changes were evaluated by hematoxylin­eosin staining. Immunohistochemical evaluations of pan­keratin, vimentin, transforming growth factor (TGF)­ß1, RhoA, RhoB, RhoC, Rho­associated coiled­coil­containing protein kinase (ROCK)I, and ROCKII expression were performed in uterine tissue. After treatment, the uterine specimens were observed to have increased uterine thickness and gland numbers in all treatment groups compared with the IUA group; however, the degree of restoration in the independent WJ­MSCs and estrogen treatment groups was better than in the combined treatment group. Immunohistochemical analysis demonstrated that pan­keratin expression was increased, and RhoA, ROCKI and TGF­ß1 expression was significantly inhibited in the WJ­MSCs and WJ­MSCs + estrogen treatment groups compared with the IUA group; however, the expression levels of these proteins were similar among all treatment groups. No change in vimentin expression was detected in any treatment group. The expression levels of RhoB, RhoC and ROCKII were clearly not affected by WJ­MSCs intervention alone. In conclusion, transplantation of WJ­MSCs may repair endometrial damage in IUA rats via TGF­ß1­mediated inhibition of RhoA/ROCKI signaling.

Dietary supplementation of barley and/or dates attenuate hypercholesterolemic-induced endometrial dysfunction in Wistar albino rats via alleviation of apoptotic pathways and enhancing oxidative capacity.

Our study was conducted to characterize the efficacy of barley and/or date palm fruits (10%) in alleviation of hypercholesterolemic endometrial insults in obese rat model. Sixty-four Wistar albino rats were randomized into eight groups (n = 8); control, hypercholesterolemic- and hypercholesterolemic-treated groups. Animals were subjected to treatment for 4 months. After sacrifice, serum and uterine tissues were collected and processed for biochemical, histological, immunohistochemical, and electron microscopic investigations. In hypercholesterolemic rats, the endometrium displayed hyperplasia with necrotic patches in the surface epithelium and its glandular lining cells. Also, there was a remarkable increase in the endometrial thickness and significant decrease in corresponding glandular numbers. Prompted by these findings, immunohistochemical localization revealed that expression of proliferating cell nuclear antigen was downregulated, while cleaved caspase-3 was upregulated in the endometrial cells in hypercholesterolemic group. Accordingly, there was remarkable depletion of antioxidant enzymatic activities associated with increased lipid peroxidation and apoptotic markers. Contradictory, supplementation of barley and/or dates to hypercholesterolemic groups showed intriguing amelioration for the histological architecture of the endometrium and balancing its oxidative redox. In conclusion, the administration of barley and/or dates confers enhanced synergistic effects in attenuation of hypercholesterolemic induced-endometrial dysfunction. This is clear evidence that endometrial amelioration was directly linked to the implication of highly potential antioxidant capacity of barley and/or dates phytochemicals, ß-glucan, polyphenols, and other trace elements, which can be utilized to establish a phyto-therapeutic strategy for activating endometrial cell regeneration. PRACTICAL APPLICATIONS: Barley and dates confer both hypoglycemic and hypocholesterolemic potentials. Therefore, their ingredients would be implicated in the amelioration of uterine functions in obese women. These favorable potentials were directly linked to the restraining of endometrial inflammation and retrieving the oxidative capacity. Furthermore, our findings demonstrated that barley and dates substantially diminished the expression of TNF-α, mitigated DNA damage and prevented leukocytic infiltration in the endometrial tissue; based on their high content of dietary phytochemicals, ß-glucan, polyphenols, and other trace elements.

The therapeutic effects of curcumin and capsaicin against cyclophosphamide side effects on the uterus in rats.

PURPOSE: To evaluate the impact of systemic cyclophosphamide treatment on the rat uterus and investigate the potential therapeutic effects of natural antioxidant preparations curcumin and capsaicin against cyclophosphamide side effects. METHODS: A 40 healthy adult female Wistar albino rats were used in this study. Rats were randomly divided into four groups to determine the effects of curcumin and capsaicin against Cyclophosphamide side effects on the uterus (n=10 in each group); Group 1 was the control group (sham-operated), Group 2 was the cyclophosphamide group, Group 3 was the cyclophosphamide + curcumin (100mg/kg) group, and Group 4 was the cyclophosphamide + capsaicin (0.5 mg/kg) group. RESULTS: Increased tissue oxidative stress and histological damage in the rat uterus were demonstrated due to the treatment of systemic cyclophosphamide chemotherapy alone. The level of tissue oxidant and antioxidant markers and histopathological changes were improved by the treatment of curcumin and capsaicin. CONCLUSION: Cytotoxic effects of natural alkylating chemotherapeutic agents like cyclophosphamide on the uterus can be prevented by curcumin and capsaicin.

The therapeutic effects of curcumin and capsaicin against cyclophosphamide side effects on the uterus in rats

Abstract Purpose: To evaluate the impact of systemic cyclophosphamide treatment on the rat uterus and investigate the potential therapeutic effects of natural antioxidant preparations curcumin and capsaicin against cyclophosphamide side effects. Methods: A 40 healthy adult female Wistar albino rats were used in this study. Rats were randomly divided into four groups to determine the effects of curcumin and capsaicin against Cyclophosphamide side effects on the uterus (n=10 in each group); Group 1 was the control group (sham-operated), Group 2 was the cyclophosphamide group, Group 3 was the cyclophosphamide + curcumin (100mg/kg) group, and Group 4 was the cyclophosphamide + capsaicin (0.5 mg/kg) group. Results: Increased tissue oxidative stress and histological damage in the rat uterus were demonstrated due to the treatment of systemic cyclophosphamide chemotherapy alone. The level of tissue oxidant and antioxidant markers and histopathological changes were improved by the treatment of curcumin and capsaicin. Conclusion: Cytotoxic effects of natural alkylating chemotherapeutic agents like cyclophosphamide on the uterus can be prevented by curcumin and capsaicin.

Intrauterine inflammation induces sex-specific effects on neuroinflammation, white matter, and behavior.

Exposure to inflammation during pregnancy has been linked to adverse neurodevelopmental consequences for the offspring. One common route through which a developing fetus is exposed to inflammation is with intrauterine inflammation. To that end, we utilized an animal model of intrauterine inflammation (IUI; intrauterine lipopolysaccharide (LPS) administration, 50µg, E15) to assess placental and fetal brain inflammatory responses, white matter integrity, anxiety-related behaviors (elevated zero maze, light dark box, open field), microglial counts, and the CNS cytokine response to an acute injection of LPS in both males and females. These studies revealed that for multiple endpoints (fetal brain cytokine levels, cytokine response to adult LPS challenge) male IUI offspring were uniquely affected by intrauterine inflammation, while for other endpoints (behavior, microglial number) both sexes were similarly affected. These data advance our understanding of sex-specific effects of early life exposure to inflammation in a translationally- relevant model.

Expression of SOX2, NANOG and OCT4 in a mouse model of lipopolysaccharide-induced acute uterine injury and intrauterine adhesions.

BACKGROUND: Activation of inflammation-mediated endometrial injury is suggested to play a decisive role in pathogenesis of intrauterine adhesion (IUA). The stem cell theory of endometrial diseases has been given a hotspot, in that human endometrial stem cells have been isolated from the endometrium. Three transcription factors that play key roles in maintaining pluripotency and self-renewal in stem cells are sex-determining region Y-box2 (SOX2), Nanog homebox (NANOG), and octamer-binding protein (OCT4), which may be responsible for the damage or repair process of uterine endometrium. We aim to investigate the expression of SOX2, NANOG and OCT4 in a mouse model of acute uterine injury induced by peritoneal injection of lipopolysaccharide (LPS) and also analyze their changes in endometrium of women with IUA. METHODS: The mouse uterine horns were collected at 0 h, 6 h, 12 h, 18 h or 24 h after a single dose of LPS or PBS injection. Meanwhile, we recruited 19 women with IUA diagnosed by hysteroscopy and 16 disease-free women as control group. Endometrial tissue samples were collected. SOX2, NANOG, and OCT4 expression were analyzed with Quantitative Real-time Polymerase Chain Reaction and Western blotting assay. RESULTS: In a mouse model of acute uterine injury, there was significant upregulation of NANOG at 6 h, SOX2 and OCT4 at 12 h compared with the values before injection or PBS injection. NANOG expression reached a peak at 6 h, while SOX2 and OCT4 peaked later at 12 h after LPS treatment. NANOG mRNA and protein expressions were significantly higher in endometrium of IUA patients compared to those of the control group. CONCLUSIONS: Expression of pluripotency factors SOX2, NANOG and OCT4 increased in a mouse model of LPS-induced acute uterine injury. NANOG peaked earlier followed by the other two factors before returning to baseline levels. NANOG but not SOX2 and OCT4 expression was overexpressed in the endometrium of women with IUA. They may be involved in the formation or restoration of IUA, and their roles in pathogenesis of IUA need to be further studied.

Evaluation of chlorhexidine hydrochloride treatment on endometrial health of normal mares.

Chlorhexidine gluconate solution is a potent antimicrobial and therefore could be used effectively for treatment of endometritis, but historically this substance has been implicated as irritating to mucous membranes, including the endometrium of the mare. The use of chlorhexidine hydrochloride suspension (Nolvasan Suspension, Zoetis, Florham Park, NJ, USA) was evaluated in the uterus of normal mares to determine if adverse effects on endometrial health were noted. Twelve healthy, adult light breed mares were included in this study. Procedures were approved by the Auburn University Institutional Animal Care and Use Committee. All mares were determined to be reproductively normal by evaluation of endometrial histopathology, cytology, and bacterial culture. Mares were randomly assigned to treatment or control groups (n = 6 per group). Each mare was treated during estrus with an intrauterine infusion of 1 g (28 mLs per tube; 35.7 mg/mL) of chlorhexidine hydrochloride suspension (treatment group) or an equal volume of lactated ringer's solution (control group) once daily for 3 consecutive days. Biopsy and cytology samples were taken 3, 7, and 14 days after completion of treatment. Cytology and biopsy samples were read by a board-certified pathologist (L.N.) blinded to treatments, and biopsy samples were graded using a standardized Kenney-Doig score. There was no difference with respect to biopsy grade, degree of endometrial fibrosis, or presence of cytologic inflammation comparing control and treatment groups (P = 0.55, 0.7, and 0.06, respectively), neither when accounting for sampling day. The suspension was visible within the uterine lumen when mares were examined with transrectal ultrasonography for up to 4 days after treatment. Treatment with chlorhexidine hydrochloride in this formulation and at this concentration does not appear to have a deleterious effect on short term endometrial health in mares.

Endometrial breakdown with sustained progesterone release involves NF-κB-mediated functional progesterone withdrawal in a mouse implant model.

Irregular uterine bleeding is a major side effect of long-acting progestogen-only contraceptives in women, and is the primary reason women discontinue their use. In this study, a mouse model of endometrial breakdown was established using a subcutaneous progesterone implant to understand how irregular bleeding begins. Although progestogens sustained decidualization, endometrial breakdown was still observed in this model. We, therefore, hypothesized that endometrial breakdown might involve functional progesterone withdrawal. Using co-immunoprecipitation assays, we observed the constitutive activation of nuclear factor kappa-b (NF-κB) p65 and its interaction with the progesterone receptor (PGR); moreover, transcriptional activity of the PGR was also repressed by NF-κB activity in primary mouse and human decidual stromal cells that mimic progesterone maintenance. Yet the ratio of PGR-B to PGR-A was not increased in the mouse model. In vivo comparison of endometrial breakdown induced by progesterone withdrawal to that seen during sustained progesterone exposure, in the presence of NF-κB inhibitors, revealed that NF-κB-mediated functional progesterone withdrawal is involved in endometrial breakdown in this implant model. These data prompt further studies to determine the homology of this functional progesterone withdrawal mechanism in human endometrium. Mol. Reprod. Dev. 83: 780-791, 2016 © 2016 Wiley Periodicals, Inc.

Neonatal Progesterone Programs Adult Uterine Responses to Progesterone and Susceptibility to Uterine Dysfunction.

In this report, we investigated the consequences of neonatal progesterone exposure on adult rat uterine function. Female pups were subcutaneously injected with vehicle or progesterone from postnatal days 3 to 9. Early progesterone exposure affected endometrial gland biogenesis, puberty, decidualization, and fertility. Because decidualization and pregnancy success are directly linked to progesterone action on the uterus, we investigated the responsiveness of the adult uterus to progesterone. We first identified progesterone-dependent uterine gene expression using RNA sequencing and quantitative RT-PCR in Holtzman Sprague-Dawley rats and progesterone-resistant Brown Norway rats. The impact of neonatal progesterone treatment on adult uterine progesterone responsiveness was next investigated using quantitative RT-PCR. Progesterone resistance affected the spectrum and total number of progesterone-responsive genes and the magnitude of uterine responses for a subset of progesterone targets. Several progesterone-responsive genes in adult uterus exhibited significantly dampened responses in neonatally progesterone-treated females compared with those of vehicle-treated controls, whereas other progesterone-responsive transcripts did not differ between female rats exposed to vehicle or progesterone as neonates. The organizational actions of progesterone on the uterus were dependent on signaling through the progesterone receptor but not estrogen receptor 1. To summarize, neonatal progesterone exposure leads to disturbances in endometrial gland biogenesis, progesterone resistance, and uterine dysfunction. Neonatal progesterone effectively programs adult uterine responsiveness to progesterone.

Estrogen decreases the expression of claudin-5 in vascular endothelial cells in the murine uterus.

Vascular endothelial (VE)-cadherin and claudin-5 are major components of the adherens and tight junctions of vascular endothelial cells, respectively, and decreases in their expression are associated with increases in endothelial paracellular permeability. In the uterus, estrogen induces endometrial edema. However, the in vivo effect of estrogen on endothelial paracellular permeability is unknown. Therefore, we studied the expression of VE-cadherin and claudin-5 in vascular endothelial cells in murine uteri stimulated by estrogen or progesterone. Ovariectomized mature mice were injected with estradiol-17ß (1 µg/mouse) or progesterone (1 mg/mouse) at intervals of 24 hours for 6 days. The frozen transverse sections of the uteri of these mice and untreated mice were stained for CD31 (vascular endothelial cell marker) plus VE-cadherin or claudin-5 using a double-immunofluorescence method. Then, the percentages of VE-cadherin- or claudin-5-positive vessels among CD31-positive vessels were examined in the uterine endometria. VE-cadherin and claudin-5 were expressed in most CD31-positive vessels in the endometria of the untreated mice. Progesterone did not affect the expression of both VE-cadherin and claudin-5 and estradiol-17ß also did not affect the VE-cadherin expression, but estradiol-17ß significantly decreased the claudin-5 expression. This decreasing effect of estradiol-17ß was detected from 24 hours later when the water content per a uterus significantly increased. The present study indicates that estrogen, but not progesterone, decreases the expression of claudin-5 in vascular endothelial cells in the murine uterine endometrium from 24 hours later, suggesting that the decrease in the claudin-5 expression contributes to the endometrial edema late after the estrogen stimulation.

A prospective randomised study of transvaginal ultrasound effects of tamoxifen and exemestane in postmenopausal women with early breast cancer.

AIM AND BACKGROUND: A reduction of gynaecological adverse events has been reported in trials comparing aromatase inhibitors with tamoxifen as adjuvant treatment in postmenopausal women with early breast cancer, but there is a paucity of randomised studies specifically investigating their effects on the uterus. We report here the results of a prospective phase III trial comparing the effects of tamoxifen and exemestane by transvaginal ultrasound (TVUS). PATIENTS AND METHODS: Postmenopausal patients with ER+ early breast cancer were randomised to receive tamoxifen 20 mg once daily or exemestane 25 mg once daily as adjuvant hormone therapy. TVUS was performed at baseline and at 6 and 12 months to measure endometrial thickness (ET) and uterine volume (UV). RESULTS: A total of 123 women were randomised to tamoxifen (n = 61) or exemestane (n = 62). A significantly higher proportion of patients in the tamoxifen group had increased ET at 6 and 12 months from randomisation compared with the exemestane group (66.1% and 64.3% versus 12.1% and 6.8%, respectively; P < 0.0001). Mean ET and UV also significantly increased with tamoxifen compared to exemestane at both time points (P < 0.01 for all comparisons). CONCLUSION: Tamoxifen is associated with endometrial thickening and increased uterine volume in a significant proportion of postmenopausal women with early breast cancer. Our study confirms the lack of endometrial effects of exemestane, which may be of interest to patients and clinicians when choosing among adjuvant endocrine options for breast cancer.

Acute uterine irritation provokes colonic motility via transient receptor potential A(1)-dependent spinal NR2B phosphorylation in rats.

BACKGROUND: Patients with inflammatory gynecological/obstetrical problems often complain of irritable bowel syndrome. The authors examined whether acute uterus irritation reflexively provokes colonic motility in rat preparations. METHODS: A modified colon manometry and striated abdominal muscle electromyogram activity in response to mustard oil (MO) instillation into the uterine horn were continuously recorded in anesthetized rats. The lumbosacral (L6-S1) dorsal horn was dissected to assess the level and the cellular location of phosphorylated NR2B subunit using Western blotting and immunofluorescence analysis, respectively. Finally, the uterine transient receptor potential A1 or spinal NR2B subunit was pharmacologically blocked to elucidate its roles. RESULTS: MO (0.1%, 0.2 ml) injected into the lower uterine horn dramatically provoked colonic hypermotility characterized by rhythmic colonic contractions (about 3-4 contractions per 10 min, n = 7) accompanied by synchronized electromyogram firing in the abdominal muscle (about 4-5 folds of control, n = 7). In addition to provoking colonic hypermotility, MO administration also up-regulated phosphorylated (about 2-3 folds of control, n = 7), but not total, NR2B expression in the dorsal horn neurons. Both intrathecal Ro 25-6981 (a selective NR2B subunit antagonist; 10 µM, 10 µl) and intrauterine HC-030031 (a selective transient receptor potential A1 receptor antagonist; 30 mg/kg, 0.2 ml) injected before the MO instillation attenuated the MO-induced colonic hypermotility and spinal NR2B phosphorylation. CONCLUSION: The comorbidity of gynecological/obstetrical and gastrointestinal problems is not coincidental but rather causal in nature, and clinicians should investigate for gynecological/urological diseases in the setting of bowel problems with no known pathological etiology.