Evaluation of pathogenicity of WT1 intron variants by in vitro splicing analysis.

BACKGROUND: Wilms tumor 1 (WT1; NM_024426) causes Denys-Drash syndrome, Frasier syndrome, or isolated focal segmental glomerulosclerosis. Several WT1 intron variants are pathogenic; however, the pathogenicity of some variants remains undefined. Whether a candidate variant detected in a patient is pathogenic is very important for determining the therapeutic options for the patient. METHODS: In this study, we evaluated the pathogenicity of WT1 gene intron variants with undetermined pathogenicity by comparing their splicing patterns with those of the wild-type using an in vitro splicing assay using minigenes. The three variants registered as likely disease-causing genes: Mut1 (c.1017-9 T > C(IVS5)), Mut2 (c.1355-28C > T(IVS8)), Mut3 (c.1447 + 1G > C(IVS9)), were included as subjects along the 34 splicing variants registered in the Human Gene Mutation Database (HGMD)®. RESULTS: The results showed no significant differences in splicing patterns between Mut1 or Mut2 and the wild-type; however, significant differences were observed in Mut3. CONCLUSION: We concluded that Mut1 and Mut2 do not possess pathogenicity although they were registered as likely pathogenic, whereas Mut3 exhibits pathogenicity. Our results suggest that the pathogenicity of intronic variants detected in patients should be carefully evaluated.

Surgical outcomes of video-assisted neck surgery for papillary thyroid carcinoma.

PURPOSE: New approaches to endoscopic thyroid surgery have been developed to improve cosmetic results, one of which is video-assisted neck surgery (VANS). The present study investigates the safety and effectiveness of thyroidectomy by VANS as oncologic surgery for papillary thyroid carcinoma (PTC). METHODS: The subjects of this retrospective study were 121 patients with PTC, who underwent hemi-thyroid lobectomy and central lymph node dissection via open surgery (n = 102) or VANS (n = 19) at Tokushima University Hospital between 2011 and 2023. We performed 1:1 propensity score matching and then compared the surgical outcomes between the two matched groups. RESULTS: Propensity score matching generated 18 distinct examination pairs. The VANS group had significantly less blood loss (P = 0.003), but a longer operative time (P < 0.001) than the open thyroidectomy group. There were two cases of transient recurrent laryngeal nerve paralysis and one case of recurrence in the lateral regional lymph nodes in the VANS group. However, no significant differences were observed in the incidence of complications (P = 0.243) or recurrence (P = 0.500) between the two groups. CONCLUSION: VANS is a safe and effective surgical procedure for PTC, but longer follow-up is needed to assess tumor recurrence.

Impact of preoperative 6-minute walk distance on long-term prognosis after esophagectomy in patients with esophageal cancer.

BACKGROUND: The 6-minute walk distance (6MWD) is a simple way of assessing exercise capacity. The purpose of this study was to investigate the relationship between preoperative 6MWD and long-term prognosis after esophagectomy. METHODS: This retrospective cohort study involved 108 patients who underwent radical esophagectomy for esophageal cancer between 2013 and 2020. The patients were classified into the short group (SG: 6MWD < 480 m) or the long group (LG: 6MWD ≥ 480 m). To adjust for the background characteristics of both groups, propensity score matching (PSM) analysis was performed and 32 patients were matched from each group. Five-year overall survival (OS) and relapse-free survival (RFS) were analyzed by the Kaplan-Meier method. The log-rank test was used to evaluate differences in survival between the groups. After adjusting for other prognostic factors, the Cox proportional hazards model was used to investigate the impact of preoperative 6MWD on long-term prognosis. RESULTS: The median follow-up period was 923 days. Thirty-three deaths were recorded during the study period. After PSM, 5-year OS following surgery was 29.2 and 66.1% (p = 0.003) and 5-year RFS was 27.9 and 58.6% (p = 0.021) in the SG and LG, respectively. In Cox proportional hazards analysis, the SG was a significant independent risk factor for OS (hazard ratio 3.33; 95% confidence interval 1.37-8.11, p = 0.008) and RFS (hazard ratio 2.30; 95% confidence interval 1.08-4.88, p = 0.030). CONCLUSION: The preoperative 6MWD is useful for evaluating exercise capacity and predicting the long-term outcome in patients undergoing esophagectomy.

Endobronchial Ultrasound Improves the Diagnosis of the Tracheobronchial Invasion of Advanced Esophageal Cancer.

BACKGROUND: Accurate diagnosis of the tracheobronchial invasion of advanced esophageal cancer is essential to select appropriate treatment and improve prognosis; however, it is difficult using the conventional modalities. This study aimed to clarify the diagnostic usefulness of convex probe endobronchial ultrasound (CP-EBUS) for the diagnosis of the tracheobronchial invasion of advanced esophageal cancer. METHODS: We conducted a cadaveric study to clarify the changes in ultrasonic and histopathologic findings in the esophageal tumor and tracheal invasion models. Additionally, we examined CP-EBUS for patients with advanced thoracic esophageal cancer in whom tracheobronchial invasion was suspected on contrast-enhanced computed tomography (CE-CT) scan. We retrospectivity evaluated the diagnosis of CP-EBUS, comparing the pathological findings and treatment outcomes. RESULTS: Cadaveric esophageal tumor and tracheal invasion models showed the disappearance of the third layer observed with CP-EBUS and histologically proven interruption of the adventitia. This indicated that the third layer corresponded with the tracheal adventitia. We examined 40 patients with advanced thoracic esophageal cancer in whom tracheobronchial invasion was suspected. The precise diagnosis was pathologically confirmed in 9 of 14 patients diagnosed with cT3 who underwent radical surgery. 20 of 26 cases diagnosed with cT4b received definitive chemoradiotherapy, and 4 cases received salvage surgery and pathologically confirmed precise diagnosis. CONCLUSION: CP-EBUS is extremely useful for diagnosing the tracheobronchial invasion of advanced esophageal cancer. It could be an effective modality for determining treatment strategies in cases with a marginal surgical indication.

Metachromins X and Y from a marine sponge Spongia sp. and their effects on cell cycle progression.

New sesquiterpene quinones, metachromins X (1) and Y (2), together with the known metachromins C (3), J (4), and T (5), were isolated as inhibitors of cell cycle progression in the HeLa/Fucci2 cells. The structure of 1 was assigned by spectroscopic data and confirmed by a total synthesis. The planar structure of 2 was determined by interpretation of spectroscopic data, whereas its absolute configuration was analyzed by a combination of chiral HPLC and CD spectroscopy. Metachromins X (1) and C (3) arrested the cell cycle progression of HeLa/Fucci2 cells at S/G2/M phase.

The sterno-tracheal distance is an important factor of anastomotic leakage of retrosternal gastric tube reconstruction after esophagectomy.

BACKGROUND: Anastomotic leakage (AL) is a serious complication after esophagectomy. The retrosternal (RS) route has been selected majorly to reduce reflux and related pneumonia and considering mediastinal recurrences. AL has been developed more in RS than posterior mediastinal (PM) route reconstruction. Therefore, we suspected the sterno-tracheal distance (STD) might be related to AL and started the selection according to the STD from 2009. METHODS: A total of 221 patients who underwent a subtotal esophagectomy with gastric tube reconstruction during January 2004-April 2017 were investigated. The patients were classified into the 'after STD selection' (A; n = 144) group and the 'before STD selection' (B, n = 77) group. The incidences of and the risk factors for AL between the two groups were compared. RESULTS: The incidence of AL was high in the B group (18.2%), and 78.6% of the patients who developed AL were treated with RS route reconstruction. The median STDs of the patients with AL and no AL were 10.3 mm and 14.5 mm, respectively (p = 0.001). These results demonstrated that the STD was a risk factor for AL in the RS route. Based on these results, 13 mm was set as the cutoff value. After STD selection, the median STD increased from 14.0 to 17.3 mm (p = 0.001), and the incidence of AL decreased significantly from 26.2 to 11.1% in the RS route (p = 0.037). CONCLUSION: The STD was the independent risk factor for AL in the RS route. RS route reconstruction should be avoided for the patients with STD < 13 mm.

The effects of the herbal medicine Daikenchuto (TJ-100) after esophageal cancer resection, open-label, randomized controlled trial.

BACKGROUND: Daikenchuto (TJ-100), a traditional Japanese herbal medicine, is widely used in Japan. Its effects on gastrointestinal motility and microcirculation and its anti-inflammatory effect are known. The purpose of this prospective randomized controlled trial was to investigate the effect of TJ-100 after esophagectomy in esophageal cancer patients. METHODS: Forty patients for whom subtotal esophageal resection for esophageal cancer was planned at our institute from March 2011 to August 2013 were enrolled and divided into two groups at the point of determination of the operation schedule after informed consent was obtained: a TJ-100 (15 g/day)-treated group (n = 20) and a control group (n = 20). The primary efficacy end-points were maintenance of the nutrition condition and the recovery of gastrointestinal function. The secondary efficacy end-points were the serum C-reactive protein (CRP) level and adrenomedullin level during the postoperative course, the incidence of postoperative complications, and the length of hospital stay after surgery. RESULTS: We examined 39 patients because one patient in the TJ-100 group was judged as having unresectable cancer after surgery. The mean age of the TJ-100 group patients was significantly older than that of the control group patients.The rate of body weight decrease at postoperative day 21 was significantly suppressed in the TJ-100 group (3.6% vs. the control group: 7.0%, p = 0.014), but the serum albumin level was not significantly different between the groups. The recovery of gastrointestinal function regarding flatus, defecation, and oral intake showed no significant between-group differences, but postoperative bowel symptoms tended to be rare in the TJ-100 group. There was no significant between-group difference in the length of hospital stay after surgery. The serum CRP level at postoperative day 3 was 4.9 mg/dl in the TJ-100 group and 6.9 mg/dl in the control group, showing a tendency of a suppressed serum CRP level in the TJ-100 group (p = 0.126). The rate of increase in adrenomedullin tended to be high postoperatively, but there was no significant difference between the two groups. CONCLUSIONS: TJ-100 treatment after esophageal cancer resection has the effects of prompting the recovery of gastrointestinal motility and minimizing body weight loss, and it might suppress the excess inflammatory reaction related to surgery.

CXCR4 Expression is Associated with Poor Prognosis in Patients with Esophageal Squamous Cell Carcinoma.

BACKGROUND: Chemokines and their receptors are known to play important roles in the tumorigenesis of many malignancies. The chemokine CXCL12 and its receptors CXCR4 and CXCR7 were suggested to be involved in cancer invasion and metastasis. The aim of this retrospective study was to evaluate the prognostic impact of the expressions of CXCL12, CXCR4 and CXCR7 in patients with esophageal squamous cell carcinoma (ESCC). METHODS: We used immunohistochemistry (IHC) and reverse transcriptase-polymerase chain reaction (RT-PCR) to evaluate the expressions of CXCL12, CXCR4, and CXCR7 in ESCC patients' tumor biopsy specimens obtained during preoperative endoscopy or surgery. These results were compared with the patients' clinicopathological parameters and survival. RESULTS: IHC was conducted for 172 patients. High expression of CXCR4 in the cytoplasm and nuclei and that of CXCR7 were associated with poor cause-specific survival (CSS) (P= .002 and .010, respectively). The specimens from 52 of the 172 patients were examined by RT-PCR and quantitative real-time PCR. The expression levels of messenger RNA (mRNA) of CXCR4 and CXCR7 were significantly increased in the tumors compared with normal esophageal mucosae (P < .0001). The expression level of mRNA of CXCR4 was associated with poor recurrence-free survival and CSS (P = .012 and .038, respectively). CONCLUSIONS: CXCR4 expression is associated with poor prognosis in patients with ESCC.

[PERIOPERATIVE ORAL MANAGEMENT FOR ESOPHAGEAL CANCER AND LUNG CANCER SURGERY].

The effectiveness of perioperative oral management in decreasing the risk of postoperative pneumonia has been reported recently. We introduced perioperative oral management for esophageal cancer and lung cancer patients in 2014 and report here its current status and effectiveness for those patients in our institute. Every 100 cases of esophageal cancer and lung cancer patients treated surgically were classified into two groups, i.e., with or without perioperative oral management, and postoperative complications were compared retrospectively. In the lung cancer group, oral management prevented postoperative pneumonia significantly and shortened the length of hospital stays after surgery in comparison with the group without oral management. In the esophageal cancer group, there was little occurrence of postoperative pneumonia in either group. Numerous esophageal cancer patients who received neoadjuvant chemotherapy developed oral mucositis and received oral care treatment before surgery. Such treatment for oral mucositis likely improved the oral environment and prevented postoperative pneumonia. Other patients have also been introduced to the importance of oral care before chemotherapy. Perioperative oral management can prevent postoperative pneumonia in esophageal cancer and lung cancer patients.

Photoactivation of the Ni-SIr state to the Ni-SIa state in [NiFe] hydrogenase: FT-IR study on the light reactivity of the ready Ni-SIr state and as-isolated enzyme revisited.

The Ni-SIr state of [NiFe] hydrogenase from Desulfovibrio vulgaris Miyazaki F was photoactivated to its Ni-SIa state by Ar(+) laser irradiation at 514.5 nm, whereas the Ni-SL state was light induced from a newly identified state, which was less active than any other identified state and existed in the "as-isolated" enzyme.

A Case of IgG4-Related Retroperitoneal Fibrosis from the Renal Pelvis Mimicking Bilateral Hydronephrosis.

We describe a 49-year-old woman who presented with continuous bilateral lumbago. As the patient's ultrasonography manifestations were very similar to those of bilateral hydronephrosis, we performed retrograde pyelography and ureteroscopy. However, apart from slight left ureteropelvic junction obstruction, there was no hydronephrosis. Since malignant disease could not be completely denied, computed tomography-guided biopsy was performed. However, the tissue did not show evidence of malignancy. As the patient continued to have lumbago, we measured serum IgG4 levels because of suspicion of retroperitoneal fibrosis secondary to IgG4-related disease, which proved to be high. Further, immunostaining of the renal pelvic biopsy samples showed IgG4-positive cells. Therefore, diagnosing IgG4-related retroperitoneal fibrosis, we administered corticosteroids. The patient responded favorably to the drug, with gradual regression of the lesion.

[Current Status and Effectiveness of Perioperative Oral Health Care Management for Lung Cancer and Esophageal Cancer Patients].

The effectiveness of perioperative oral health care management to decrease the risk of postoperative pneumonia have been reported lately. Since 2014, we introduced perioperative oral health care management for lung cancer and esophageal cancer patients. We report current status and effectiveness of perioperative oral health care management for lung cancer and esophageal cancer patients. Every 100 cases of lung cancer and esophageal cancer patients treated by surgery were classified 2 group with or without perioperative oral health care management and compared about postoperative complications retrospectively. In the lung cancer patients, the group with oral health care management could prevent postoperative pneumonia significantly and had shorter length of hospital stay than the group without oral health care management. In the esophageal cancer patients, there was little occurrence of postoperative pneumonia without significant difference between both group with or without oral health care management. A large number of esophageal cancer patients received neo-adjuvant chemotherapy and some patients developed oral mucositis and received oral care treatment before surgery. Treatment for oral mucositis probably improved oral environment and affected prevention of postoperative pneumonia. Perioperative oral health care management can prevent postoperative pneumonia of lung cancer and esophageal cancer patients by improvement of oral hygiene.

Silicone stent placement for tracheal stenosis induced by a giant goiter due to Graves' disease: a case report.

Background: Although thyroid tumors with tracheal stenosis are occasionally encountered, severe tracheal stenosis caused by benign thyroid tumors is rare. We herein describe a case in which a silicone tracheal stent was placed for severe tracheal stenosis induced by a giant goiter due to Graves' disease. Case Description: A 93-year-old woman had been receiving thiamazole treatment for Graves' disease with a thyroid goiter for 32 years. She emergently presented to the hospital with sudden difficulty breathing and the temporary loss of consciousness. Although marked stridor was heard, the patient's respiratory status was stable in the first visit. Computed tomography revealed a giant thyroid goiter that extended to the mediastinum. The trachea was compressed by the sternal notch and thyroid gland, resulting in severe stenosis, and the tracheal lumen was only 1 mm. Surgical thyroidectomy was expected to be difficult due to the high risk of complications associated with the large size of the goiter and advanced age of the patient. Therefore, we decided to place a tracheal stent. A silicone stent (Dumon tube®) was inserted into the site of tracheal stenosis under general anesthesia. After stent placement, respiratory distress symptoms improved, and no complications were observed. Three months after stent placement, the stent opening side was narrowed due to defective granulation and, thus, was cauterized with argon plasma coagulation. Conclusions: We encountered a patient who was treated by tracheal silicone stent placement for severe tracheal stenosis induced by a giant goiter due to Graves' disease. A silicone stent effectively secures the airway for benign thyroid tumors that cause severe airway stenosis.

Inhibition of postprandial hyperglycemia by either an insulin-dependent or -independent drug reduces the expression of genes related to inflammation in peripheral leukocytes of OLETF rats.

Treatment with the dipeptidyl peptidase-4 inhibitor, anagliptin, or with the α-glucosidase inhibitor, miglitol, reduced the oral sucrose load-inducible expression of interleukin (IL)-1ß, IL-18, tumor necrosis factor-α, S100a8, S100a9, S100a11, IL-1R2, IL-1Rn and tumor necrosis factor receptor 2 genes in peripheral leukocytes of Otsuka Long-Evans Tokushima fatty (OLETF) rats at the stage of impaired glucose tolerance. Inhibiting postprandial hyperglycemia reduced the expression of genes related to inflammation in peripheral leukocytes of OLETF rats.

Botulinum toxin type A injection for neurogenic detrusor overactivity: clinical outcome in Japanese patients.

OBJECTIVES: To report our experience with intravesical injection of botulinum toxin type A into the detrusor muscle of patients with neurogenic detrusor overactivity secondary to suprasacral spinal cord lesions or multiple sclerosis. METHODS: Between January 2003 and March 2011, 11 patients (aged 23-75 years) were treated with 40 injections of botulinum toxin type A 300 U. The patients were followed up for 4, 8 and 12 weeks after treatment. The King's Health Questionnaire was administered and cystometric studies were carried out at baseline and 8 weeks after treatment. RESULTS: A total of six women and five men were treated. Analysis of the King's Health Questionnaire showed a significant improvement in eight of the nine domain scores at 8 weeks from baseline. On cystometric studies, the mean maximum cystometric capacity increased significantly in all patients at 8 weeks from baseline (P < 0.001). Bladder compliance also increased significantly (P < 0.001). The number of urinary incontinence episodes per day improved significantly from baseline after injection (4 weeks, P < 0.001; 8 weeks, P < 0.001; 12 weeks, P < 0.001). Lack of efficacy appeared 7.15 ± 3.4 months after treatment. CONCLUSIONS: Injection of botulinum toxin type A into the detrusor muscle of patients with neurogenic detrusor overactivity secondary to suprasacral spinal cord lesions or multiple sclerosis consistently improves bladder control and quality of life.

New insights into the oxidation process from neutron and X-ray crystal structures of an O2-sensitive [NiFe]-hydrogenase.

[NiFe]-hydrogenase from Desulfovibrio vulgaris Miyazaki F is an O2-sensitive enzyme that is inactivated in the presence of O2 but the oxidized enzyme can recover its catalytic activity by reacting with H2 under anaerobic conditions. Here, we report the first neutron structure of [NiFe]-hydrogenase in its oxidized state, determined at a resolution of 2.20 Å. This resolution allowed us to reinvestigate the structure of the oxidized active site and to observe the positions of protons in several short hydrogen bonds. X-ray anomalous scattering data revealed that a part of the Ni ion is dissociated from the active site Ni-Fe complex and forms a new square-planar Ni complex, accompanied by rearrangement of the coordinated thiolate ligands. One of the thiolate Sγ atoms is oxidized to a sulfenate anion but remains attached to the Ni ion, which was evaluated by quantum chemical calculations. These results suggest that the square-planar complex can be generated by the attack of reactive oxygen species derived from O2, as distinct from one-electron oxidation leading to a conventional oxidized form of the Ni-Fe complex. Another major finding of this neutron structure analysis is that the Cys17S thiolate Sγ atom coordinating to the proximal Fe-S cluster forms an unusual hydrogen bond with the main-chain amide N atom of Gly19S with a distance of 3.25 Å, where the amide proton appears to be delocalized between the donor and acceptor atoms. This observation provides insight into the contribution of the coordinated thiolate ligands to the redox reaction of the Fe-S cluster.

Impact of postoperative physical activity on the development of pneumonia in the subacute phase after esophagectomy in patients with esophageal cancer: A retrospective cohort study.

PURPOSE: Physical activity is important to improve recovery following surgery. This study investigated the impact of physical activity on the development of pneumonia after radical esophagectomy in patients with thoracic esophageal cancer in the subacute phase from postoperative day 11 to hospital discharge. METHODS: This retrospective cohort study included 83 patients who underwent radical esophagectomy for esophageal cancer between 2016 and 2022. Physical activity was measured using an activity tracker, and the average number of steps between postoperative days 8 and 10 was examined. The primary outcome was pneumonia (Clavien-Dindo classification 2 or higher) developing between postoperative day 11 and hospital discharge. We used the receiver operating characteristic (ROC) curve analysis to calculate the optimal cutoff value of physical activity that can predict the development of pneumonia and define low physical activity. We used logistic regression analysis to investigate the impact of low physical activity on postoperative pneumonia. RESULTS: Pneumonia developed in 10 patients (12.0%) during the observation period. The optimal cutoff value of physical activity for predicting pneumonia was 1494 steps per day (sensitivity: 60.0%, specificity: 89.0%, area under the curve: 0.743). In multivariate analysis, low physical activity was an independent predictor of incident pneumonia [odds ratio: 12.10, 95% confidence interval: 2.21-65.90, p = 0.004], with adjustment for age, gastric tube reconstruction route, and postoperative recurrent nerve palsy. CONCLUSIONS: Physical activity following radical esophagectomy in patients with thoracic esophageal cancer was an independent predictor of the development of pneumonia in the subacute phase after radical esophagectomy.

Sentinel lymph node biopsy using intraoperative indocyanine green fluorescence imaging navigated with preoperative CT lymphography for superficial esophageal cancer.

BACKGROUND: The sentinel lymph node (SLN) concept has been gaining attention for gastrointestinal neoplasms but remains controversial for esophageal cancer. This study evaluated the feasibility of SLN identification using intraoperative indocyanine green (ICG) fluorescence imaging (IGFI) navigated by preoperative computed tomographic lymphography (CTLG) to treat superficial esophageal cancer. METHODS: Subjects comprised 20 patients clinically diagnosed with superficial esophageal cancer. Five minutes after endoscopic submucosal injection of iopamidol around the primary lesion using a four-quadrant injection pattern with a 23-gauge endoscopic injection sclerotherapy needle, three-dimensional multidetector computed tomography was performed to identify SLNs and lymphatic routes. ICG solution was injected intraoperatively around the tumor. Fluorescence imaging was obtained by infrared ray electronic endoscopy. Thoracoscope-assisted standard radical esophagectomy with lymphadenectomy was performed to confirm fluorescent lymph nodes detected by CTLG. RESULTS: Lymphatic vessels and SLNs were identified preoperatively using CTLG in all cases. Intraoperative detection rates were 100% using CTLG and 95% using IGFI. Lymph node metastases were found in four cases, including one false-negative case with SLNs occupied by bulky metastatic tumor that were not enhanced with both methods. The other 19 cases, including three cases of metastatic lymph nodes, were accurately identified by both procedures. CONCLUSIONS: Preoperative CTLG visualized the correct number and site of SLNs in surrounding anatomy during routine computed tomography to evaluate distant metastases. Referring to CTLG, SLNs were identified using IGFI, resulting in successful SLN navigation and saving time and cost. This method appears clinically applicable as a less-invasive method for treating superficial esophageal cancer.

Sensory neurone-specific receptor-mediated regulation of micturition reflex in urethane-anaesthetized rats.

OBJECTIVE: • To investigate the effect of sensory neurone-specific receptors (SNSRs) activation on the micturition reflex in rats. MATERIALS AND METHODS: • Continuous cystometrograms (CMGs, 0.04 mL/min) were performed in female Sprague-Dawley rats under urethane anaesthesia. • After stable micturition cycles were established, a selective rat SNSR1 agonist, bovine adrenal medulla 8-22 (BAM8-22), was administered intravenously (i.v.) or intrathecally (i.t.) in normal rats or rats pretreated with capsaicin 4 days before the experiments. • Micturition variables were recorded and compared before and after drug administration. RESULTS: • Administration (i.v.) of BAM8-22 (3-100 µg/kg) significantly increased intercontraction intervals in a dose-dependent fashion, but did not affect residual urine or baseline pressure at any doses tested. • Administration (i.t.) of BAM8-22 (0.01-0.3 µg) also increased intercontraction intervals in a dose-dependent fashion, but did not affect residual urine or baseline pressure at any doses tested. • These inhibitory effects of i.v. (30 µg/kg) or i.t. (0.3 µg) administration of BAM8-22 still occurred after capsaicin pretreatment. CONCLUSIONS: • These results indicate that in urethane-anaesthetized rats activation of SNSRs can inhibit the micturition reflex via pathways independent of capsaicin-sensitive C-fibres. • Thus SNSRs could be a potential target for the treatment of bladder dysfunction, e.g. overactive bladder.

Effect of silodosin on detrusor overactivity in the male spontaneously hypertensive rat.

UNLABELLED: Recently, several studies have suggested that detrusor overactivity (DO) is the result of bladder ischaemia. Hypertension could affect pelvic arterial blood flow, resulting in loss of smooth muscle in the bladder with resultant loss of bladder compliance. Spontaneously hypertensive rats are considered a valuable tool for exploring the pathogenesis of DO. Some reports indicate that α(1) adrenoceptor antagonists improve chronic ischaemia of the lower urinary tract in patients with LUTS, with concomitant improvement of their symptoms as well as improvement of DO through an increased bladder blood flow (BBF) in the rat with bladder outlet obstruction. However, the mechanism of improvement of silodosin on storage or irritative symptoms is not well investigated and is still unclear. Silodosin prevents hypertension-related DO in the SHR via several possible mechanisms. One possible mechanism of the efficacy of silodosin to the DO includes the improvement of the BBF. OBJECTIVE: To investigate the effect of the α(1A) selective adrenoceptor antagonist, silodosin, on hypertension-related detrusor overactivity (DO) and its possible mechanism in spontaneously hypertensive rats (SHRs). MATERIALS AND METHODS: Twelve-week-old male SHRs received treatment with silodosin (100 µg/kg perorally) once daily for 6 weeks; vehicle-treated Wistar rats and vehicle-treated SHRs were used for our study. Six weeks after silodosin treatment, voiding functions were estimated by voiding behaviour and cystometric studies in all groups. The bladder blood flow was measured by the hydrogen clearance method, and tissue levels of nerve growth factor (NGF) and calcitonin gene-related peptide (CGRP) were measured by enzyme-linked immunosorbent assay (ELISA). Furthermore, the expressions of α1 adrenoceptor subtype mRNAs in the bladder were investigated by real-time PCR method. RESULTS: The SHRs showed significant increases in blood pressure, micturition frequency and tissue levels of NGF and CGRP in the bladder. Moreover, the SHRs showed significant decreases in bladder blood flow and single voided volume estimated by both voiding behaviour and cystometric studies compared with those in the Wistar rats. Six weeks of treatment with silodosin significantly ameliorated hypertension-related alterations of these variables with concomitant small changes of blood pressure. The expression levels of α1 adrenoceptor subtype mRNAs in the bladder were similar in all the groups and the rank order was α1A = α1D > α1B in all groups. However, there were no significant differences in the expressions of α(1A) adrenoceptor mRNAs between any groups. CONCLUSION: The data in the present study suggest that silodosin normalizes hypertension-related DO in SHRs, which could be related to its effect on the increased blood flow in the bladder.