Transient receptor potential ankyrin 1 channels in the bladder mediate low temperature elicited bladder overactivity in rats.

AIMS: This study aimed to investigate whether pathways involving transient receptor potential ankyrin 1 (TRPA1) channels in the urinary bladder mediate the bladder overactivity elicited by exposure to a low temperature in rats. METHODS: At postnatal week 10, female Sprague-Dawley (SD) rats were intraperitoneally injected with the TRPA1 channel antagonist, HC030031, at room temperature (RT) and subsequently exposed to low temperature (LT). Bladder specimens treated with HC030031 were evaluated for contractions through cumulative addition of the TRPA1 channel agonist trans-cinnamaldehyde. Two days before cystometric investigation, small interfering RNA (siRNA) targeting TRPA1 was transfected into urinary bladders. Then, cystometric investigations were performed on rats subjected to TRPA1 siRNA transfection at both RT and LT. Expression of TRPA1 channels in the urinary bladder was assessed through immunohistochemistry and real-time reverse transcription-polymerase chain reaction. RESULTS: At RT, micturition patterns were unaffected by HC030031 treatment. However, upon exposure to LT, rats treated with HC030031 exhibited a reduction of LT-elicited bladder overactivity, as evidenced by inhibited decreases in voiding interval, micturition volume, and bladder capacity. Additionally, HC030031 inhibited trans-cinnamaldehyde-induced contractions. Immunohistochemical analysis showed the presence of TRPA1 channels in the urinary bladder. Notably, rats with TRPA1 siRNA-transfected bladders could partially inhibit bladder overactivity during LT exposure. CONCLUSIONS: These findings indicate that pathways involving TRPA1 channels expressed in the urinary bladder could mediate the LT-elicited bladder overactivity.

[Idiopathic Thrombocytopenia Purpura After Pembrolizumab Treatment Against Locally Recurrent Bladder Cancer : A Case Report].

A man in his 70s visited our hospital for gross hematuria. He was diagnosed with invasive urothelial carcinoma (cT3N2M0) and underwent total cystectomy and ileum conduit construction after three courses of neoadjuvant chemotherapy. Eight months after the operation, the disease reoccurred in the pelvic lesion. He received pembrolizumab therapy but developed idiopathic thrombocytopenic purpura (ITP) immediately before the ninth course of administration; and, treatment was discontinued. Recovery of symptoms and normalization of blood test data were achieved 3.5months after starting steroid treatment. Reduction of recurrent disease has been maintained for 2 years.

Cold stress-induced bladder overactivity in type 2 diabetic mellitus rats is mitigated by the combination of a M3 -muscarinic antagonist and a ß3 -adrenergic agonist.

OBJECTIVES: Goto-Kakizaki (GK) rats with type 2 diabetes mellitus respond to low temperature (LT) environments with bladder overactivity, including increased voiding frequency and decreased voiding interval and micturition volume. We determined if bladder overactivity could be inhibited by treatment with the combination of a M3 -muscarinic receptor antagonist and a ß3 -adrenergic receptor agonist. METHODS: Ten-week-old female GK rats were fed a high-fat diet for 4 weeks. Cystometric investigations were conducted at room temperature (RT, 27 ± 2°C). The rats were then intraperitoneally administered the vehicle, the M3 -muscarinic receptor antagonist solifenacin, the ß3 -adrenergic agonist mirabegron, or a combination of solifenacin and mirabegron. Ten minutes after the administrations, the rats were transferred to the LT environment (4 ± 2°C), where the cystometric measurements were continued. The expressions of both M3 -muscarinic and ß3 -adrenergic receptors were investigated. RESULTS: After transfer from RT to LT, both voiding interval and bladder capacity of the vehicle-, solifenacin-, or mirabegron-treated rats were significantly decreased. However, the combination of solifenacin and mirabegron significantly mitigated the bladder overactivity. While both M3 -muscarinic and ß3 -adrenergic receptors were detected, the expression of M3 -muscarinic receptor mRNA was significantly higher than that of ß3 -adrenergic receptor mRNA. CONCLUSIONS: The cold stress-induced bladder overactivity was not improved by either the M3 -muscarinic receptor antagonist or the ß3 -adrenergic receptor agonist alone. However, the combined treatment mitigated the cold stress responses. Combined therapy with M3 -muscarinic antagonists and ß3 -adrenergic agonists could reduce side effects and improve the quality of life for diabetic patients with bladder overactivity.

Autologous Bilayered Adipose-Derived Mesenchymal Cell-Gelatin Sheets Reconstruct Ureters in Rabbits.

Repair of ureteral defects or strictures due to disease or trauma is usually dependent upon surgery that often requires either reoperation or an alternative treatment. By taking advantage of tissue engineering and regenerative techniques, it may be possible to define new approaches to ureteral repair. In this study, we fabricated autologous bilayered adipose-derived mesenchymal cell (AMC)-gelatin sheets and transplanted them into rabbits to replace surgically excised ureteral segments. AMCs harvested from abdominal adipose tissues of female New Zealand white rabbits were cultured on collagen-coated dishes and labeled with PKH26, a red fluorescent dye, for later identification. Monolayers of the cultured PKH26-labeled AMCs were detached and applied to gelatin hydrogel sheets. Two gelatin sheets were then united with the AMC monolayers apposed together, forming a bilayered AMC-gelatin sheet. Following each partial ureterectomy, a bilayered autologous AMC-gelatin sheet was transplanted, joining the proximal and distal ends of the remaining ureter (n = 9). Control animals underwent the same procedure except that the transplant was achieved with a bilayered acellular-gelatin sheet (n = 9). At 4 and 8 weeks after transplantation, the proximal regions of ureters treated with the control bilayered acellular-gelatin sheets exhibited flexures and dilations, which are not characteristic of unoperated ureters. In contrast, the bilayered AMC-gelatin sheet-transplanted rabbits did not have ureteral flexures or dilations. About midway between the proximal and distal ends, both the control and experimental reconstructed ureteral walls had smooth muscle layers; however, those in the experimental reconstructed ureteral walls were significantly thicker and better organized than those in the control reconstructed ureteral walls. Some AMCs differentiated into smooth muscle marker-positive cells. The experimental ureteral walls contained smooth muscle cells derived from the PKH26-labeled AMCs and others that were derived through migration and differentiation of cells from the remaining proximal and distal ends of the original ureter. In addition, the lumina of the 8-week reconstructed ureteral tissues in experimental rabbits did not show histological strictures as seen in the control ureters. These results suggest that the bilayered AMC-gelatin sheets have the potential to replace defective tissues and/or reconstruct damaged ureters. Impact Statement To reconstruct ureter tissues following partial ureterectomy, we fabricated bilayered adipose-derived mesenchymal cell (AMC)-gelatin sheets based on cell sheet engineering principles. The bilayered AMC-gelatin sheets were transplanted into rabbits to replace a surgically excised ureteral segment. At 4 and 8 weeks after, the ureters that received bilayered AMC-gelatin sheets did not exhibit severe flexures, dilations, or strictures. The experimental ureteral walls had smooth muscle marker-positive cells that were differentiated from the AMCs, and similar cells were present in the adjacent intact ureteral tissues. Therefore, the bilayered AMC-gelatin sheets have the potential to reconstruct ureters damaged through disease or trauma.

[A CASE OF PRIMARY MUCOSA-ASSOCIATED LYMPHOID TISSUE (MALT) LYMPHOMA OF THE URINARY BLADDER].

A 68-year-old female presented with macroscopic hematuria. Cystoscopy revealed a wide-based submucosal mass. Computed tomography revealed a 3.5 × 2.5-cm solitary mass situated from the trigone to the left lateral bladder wall and the left hydroureter and hydronephrosis. T2-weighted magnetic resonance imaging (MRI) revealed low intensity, and diffusion-weighed MRI showed increased diffusion without invasion. The bladder tumor was immediately resected transurethrally. Histological diagnosis of the tissue obtained by transurethral resection was extranodal marginal zone B cell lymphoma of MALT. Positron emission tomography-CT showed no lesions other than the bladder tumor. The patient was diagnosed with stage-IE lymphoma of the bladder (Ann Arbor classification). Radiotherapy was performed at the bladder and pelvis (30 Gy) with six courses of rituximab (375 mg/m2). No local or distant recurrence after a 48-month follow-up was noted.

[A Case Report of 2,8-Dihydroxyadenine Urolithiasis].

We report a case of 2,8-dihydroxyadenine (DHA) urolithiasis in a 65-year-old male. He initially visited another institution because right hydronephrosis was revealed in a medical checkup. Computed tomography demonstrated radiolucent right renal stones. We performed percutaneous nephrolithotripsy and flexible transurethral lithotripsy and removed the stones successfully. An analysis of the stone fragments revealed 2,8-DHA urolithiasis. 2,8-DHA stones are relatively rare and caused by adenine phosphoribosyltransferase deficiency.

Therapeutic effects of Choreito, a traditional Japanese (Kampo) medicine, on detrusor overactivity induced by acetic acid in rats.

Choreito (CRT), a traditional Japanese (Kampo) medicine, is widely used for the treatment of overactive bladder (OAB) and other lower urinary tract symptoms in Japan. This study aimed to identify the effects and therapeutic mechanism of CRT on the improvement of detrusor overactivity (DO) using an experimental rat model. Forty-five female Sprague-Dawley rats were equally divided into three groups: intravesical saline instillation with normal food (normal group), intravesical acetic acid (AA) instillation with normal food (AA group), and intravesical AA instillation with CRT (AA with CRT group). To induce a decrease in bladder capacity, instillation of 0.2% AA was used based on prior studies. Cystometric investigation was employed to clarify the effects of AA and CRT. Microcirculation was performed using a laser blood flowmeter, and the localization of hypoxia-inducible factor 1α (HIF1α) was assessed by immunohistochemistry. The bladder capacities of the normal, AA, and AA with CRT groups were 1.2 ± 0.3 mL, 0.4 ± 0.1 mL, and 0.8 ± 0.1 mL, respectively. CRT significantly attenuated AA irritation of the urinary bladder and exerted protective effects on basal pressure, micturition pressure, micturition interval, and micturition volume. Furthermore, CRT could prevent the excess blood flow and edematous change under the urothelium induced by intravesical AA instillation. No obvious changes in immunohistochemical HIF1α staining were observed among the groups. CRT attenuated DO induced by intravesical AA instillation in a rat experimental model. CRT might impart therapeutic effects on OAB via the mitigation of urothelial damage and regulation of excess blood flow.

Nicotine-induced hypoxia in rat urothelium deteriorates bladder storage functions.

AIMS: To measure the effects of nicotine on lower urinary tract symptoms (LUTS), bladder blood flow, and the urothelial markers hypoxia-inducible factor 1α (HIF1α), uroplakin III (UPIII), and aquaporin 3 (AQP3). METHODS: Ten-week-old female Sprague Dawley rats were subcutaneously injected with 2 mg/kg nicotine (n = 17) or vehicle (control, n = 18) twice daily for 13 days. Some nicotine-treated rats (n = 10) were injected daily with 1 mg/kg tadalafil for the last 6 days of nicotine treatment. One day before cystometry, the bladders of some nicotine-treated and control rats were instilled with 0.08% acetic acid. Urinary frequency and volume were measured 1 day after treatment. Blood flow in the bladder neck was measured, and the urothelia were immunochemically assayed for HIF1α, UPIII, and AQP3. RESULTS: Following acetic acid treatment, both voiding interval and micturition volume of the nicotine-treated rats were significantly lower than controls. Nicotine-treated rats had lower blood flow than controls, and the urothelial expression of HIF1α was higher than controls. Simultaneously, the expressions of UPIII and AQP3 were decreased. Tadalafil treatment increased bladder blood flow, and nicotine-treated rats had increased voiding interval and micturition volume. Further, the expression of HIF1α decreased, and both UPIII and AQP3 levels increased. CONCLUSIONS: Nicotine-treated rats stimulated by intravesicular acetic acid instillation exhibited deterioration of bladder storage functions. Changes in tissue markers in the nicotine-treated rats were consistent with hypoxia and loss of urothelial function. Restoration of blood flow reversed the nicotine effects. Nicotine may induce LUTS through reduced bladder blood flow and urothelial hypoxia.

Biofabricated Structures Reconstruct Functional Urinary Bladders in Radiation-Injured Rat Bladders.

The ability to repair damaged urinary bladders through the application of bone marrow-derived cells is in the earliest stages of development. We investigated the application of bone marrow-derived cells to repair radiation-injured bladders. We used a three-dimensional bioprinting robot system to biofabricate bone marrow-derived cell structures. We then determined if the biofabricated structures could restore the tissues and functions of radiation-injured bladders. The bladders of female 10-week-old Sprague-Dawley (SD) rats were irradiated with 2-Gy once a week for 5 weeks. Adherent and proliferating bone marrow-derived cells harvested from the femurs of male 17-week-old green fluorescence protein-transfected Tg-SD rats were cultured in collagen-coated flasks. Bone marrow-derived cell spheroids were formed in 96-well plates. Three layers of spheroids were assembled by the bioprinter onto a 9 × 9 microneedle array. The assembled spheroids were perfusion cultured for 7 days, and then the microneedle array was removed. Two weeks after the last radiation treatment, the biofabricated structures were transplanted into an incision on the anterior wall of the bladders (n = 10). Control rats received the same surgery but without the biofabricated structures (sham-structure, n = 12). At 2 and 4 weeks after surgery, the sham-structure control bladder tissues exhibited disorganized smooth muscle layers, decreased nerve cells, and significant fibrosis with increased presence of fibrosis-marker P4HB-positive cells and hypoxia-marker hypoxia-induced factor 1α (HIF1α)-positive cells. The transplanted structures survived within the recipient tissues, and blood vessels extended within them from the recipient tissues. The bone marrow-derived cells in the structures differentiated into smooth muscle cells and formed smooth muscle clusters. The recipient tissues near the transplanted structures had distinct smooth muscle layers and reconstructed nerve cells, and only minimal fibrosis with decreased presence of P4HB- and HIF1α-positive cells. At 4 weeks after surgery, the sham-structure control rats exhibited significant urinary frequency symptoms with irregular and short voiding intervals, and low micturition volumes. In contrast, the structure-transplanted rats had regular micturition with longer voiding intervals and higher micturition volumes compared with the control rats. Furthermore, the residual volume of the structure-transplanted rats was lower than for the controls. Therefore, transplantation of biofabricated bone marrow-derived cell structures reconstructed functional bladders.

Combined treatment with a ß3 -adrenergic receptor agonist and a muscarinic receptor antagonist inhibits detrusor overactivity induced by cold stress in spontaneously hypertensive rats.

AIMS: This study determined if combined treatment with the muscarinic receptor (MR) antagonist solifenacin and the ß3 -adrenergic receptor (AR) agonist mirabegron could inhibit detrusor overactivity induced by cold stress in spontaneously hypertensive rats (SHRs). METHODS: Thirty-two female 10-week-old SHRs were fed an 8% NaCl-supplemented diet for 4 weeks. Cystometric measurements of the unanesthetized, unrestricted rats were performed at room temperature (RT, 27 ± 2°C) for 20 min. The rats were then intravenously administered vehicle, 0.1 mg/kg solifenacin alone, 0.1 mg/kg mirabegron alone, or the combination of 0.1 mg/kg mirabegron and 0.1 mg/kg solifenacin (n = 8 each group). Five minutes later, the treated rats were exposed to low temperature (LT, 4 ± 2°C) for 40 min. Finally, the rats were returned to RT. After the cystometric investigations, the ß3 -ARs and M3 -MRs expressed within the urinary bladders were analyzed. RESULTS: Just after transfer from RT to LT, vehicle-, solifenacin-, and mirabegron-treated SHRs exhibited detrusor overactivity that significantly decreased voiding interval and bladder capacity. However, treatment with the combination of solifenacin and mirabegron partially inhibited the cold stress-induced detrusor overactivity patterns. The decreases of voiding interval and bladder capacity in the combination-treated rats were significantly inhibited compared to other groups. Within the urinary bladders, there were no differences between expression levels of M3 -MR and ß3 -AR mRNA. The tissue distribution of M3 -MRs was similar to that of the ß3 -ARs. CONCLUSIONS: This study suggested that the combination of solifenacin and mirabegron act synergistically to inhibit the cold stress-induced detrusor overactivity in SHRs. Neurourol. Urodynam. 36:1026-1033, 2017. © 2016 The Authors. Neurourology and Urodynamics Published by Wiley Periodicals, Inc.

[A Case of Granulomatous Orchitis].

A 54-year-old man presented with slight pain and swelling of the right scrotum. On performing scrotal ultrasonography, the right testis showed swelling and diffused hypoechogenicity compared with the left normal testis. T2-weighted magnetic resonance imaging (MRI) revealed swelling and low intensity areas in the right testis. Diffusion-weighted MRI revealed increased diffusion in the right testis. A testicular tumor was suspected and right high orchitectomy was performed. Histopathological diagnosis was granulomatous orchitis. To our knowledge, this is the 22nd case in Japan.

Pathways Involving Beta-3 Adrenergic Receptors Modulate Cold Stress-Induced Detrusor Overactivity in Conscious Rats.

OBJECTIVE: To investigate pathways involving beta-3 adrenergic receptors (ARs) in detrusor overactivity induced by cold stress, we determined if the beta-3 AR agonist CL316243 could modulate the cold stress-induced detrusor overactivity in normal rats. METHODS: Two days prior to cystometric investigations, the bladders of 10-week-old female Sprague-Dawley rats were cannulated. Cystometric measurements of the unanesthetized, unrestricted rats were taken to estimate baseline values at room temperature (RT, 27 ± 2 °C) for 20 min. They were then intravenously administered vehicle, 0.1, or 1.0 mg/kg CL316243 (n = 6 in each group). Five minutes after the treatments, they were gently and quickly transferred to the low temperature (LT, 4 ± 2 °C) room for 40 min where the cystometric measurements were again made. Afterward, the rats were returned to RT for final cystometric measurements. The cystometric effects of CL316243 were also measured at RT (n = 6 in each group). RESULTS: At RT, both low and high dose of CL316243 decreased basal and micturition pressure while the high dose (1.0 mg/kg) significantly increased voiding interval and bladder capacity. During LT exposure, the high dose of CL316243 partially reduced cold stress-induced detrusor overactivity characterized by increased basal pressure and urinary frequency. The high drug dose also significantly inhibited the decreases of both voiding interval and bladder capacity compared to the vehicle- and low dose (0.1 mg/kg)-treated rats. CONCLUSION: A high dose of the beta-3 agonist CL316243 could modulate cold stress-induced detrusor overactivity. Therefore, one of the mechanisms in cold stress-induced detrusor overactivity includes a pathway involving beta-3 ARs.

Expression of 5-Hydroxytryptamine Receptors in Human Urinary Bladders with Benign Prostatic Hyperplasia.

INTRODUCTION: This study investigated the mRNA expression pattern and distribution of 5-hydroxytryptamine (5-HT) receptors 5-HT2A, 5-HT2B, 5-HT3A, 5-HT4, and 5-HT7 within the urothelium and detrusor of normal bladder tissue and in the urothelium of bladders from patients with benign prostatic hyperplasia (BPH). METHODS: Normal urinary bladder specimens were obtained from 13 patients undergoing radical cystectomy due to bladder cancer (normal group) and BPH specimens were obtained from 27 benign prostatic obstruction patients receiving transurethral prostatectomy or retropubic prostatectomy. Receptor subtype mRNA expression was determined by real-time reverse transcription polymerase chain reaction on urothelium, detrusor, and whole mucosal preparations. Receptor distribution was determined by immunohistochemistry. RESULTS: In normal tissues, expressions of 5-HT2B and 5-HT7 receptor mRNAs in the urothelium, detrusor, and whole mucosa were greater than the average expression for all receptor subtype mRNAs. 5-HT2B receptor protein was distributed in the apical urothelium and among the detrusor smooth muscle layers. In contrast, the 5-HT7 receptors were within the urothelium middle cell layers and detrusor smooth muscle cells. The expression pattern of each 5-HT receptor subtype mRNA within the BPH urothelium was similar to that in the normal urothelium. The expression level of 5-HT2A receptor mRNA in the BPH group was significantly lower than the normal group; however, the expressions of both 5-HT3A and 5-HT7 mRNAs were significantly higher. The expressions of both 5-HT2B and 5-HT4 mRNAs were not significantly different between the normal and BPH groups. CONCLUSION: In normal urinary bladders, the expressions of both 5-HT2B and 5-HT7 mRNAs were higher compared to the 5-HT2A, 5-HT3A, and 5-HT4 mRNAs. The distributions of 5-HT2B and 5-HT7 receptors were different in the urothelium and detrusor layers. The 5-HT3A and 5-HT7 receptor mRNAs in the BPH group were significantly higher compared to the normal urothelium, while the 5-HT2A mRNA was significantly lower. FUNDING: Asahi Kasei Pharma Corporation.

Transient receptor potential channel superfamily: Role in lower urinary tract function.

Lower urinary tract symptoms associated with neurogenic bladder and overactive bladder syndrome are mediated in part by members of the transient receptor potential channel superfamily. The best studied member of this superfamily is the vanilloid receptor. Other transient receptor potential channels, such as the melastatin receptor and the ankyrin receptor, are also active in the pathogenesis of lower urinary tract dysfunction. However, the detailed mechanisms by which the transient receptor potential channels contribute to lower urinary tract symptoms are still not clear, and the therapeutic benefits of modulating transient receptor potential channel activity have not been proved in the clinical setting. In the present review, to better understand the pathophysiology and therapeutic potential for lower urinary tract symptoms, we summarize the presence and role of different members of the transient receptor potential channel superfamily in the lower urinary tract.

Engineered bone marrow-derived cell sheets restore structure and function of radiation-injured rat urinary bladders.

Previously, we reported that implantation of isolated single bone marrow-derived cells into radiation-injured urinary bladders could restore structure and function. However, injections of isolated single cells had some limitations. Thus, in this study, we produced bone marrow-derived cell sheets in temperature-responsive culture dishes that release the monolayer sheets intact. We then determined whether the produced cell sheets could restore function to irradiated urinary bladders. Twenty female 10-week-old Sprague-Dawley (SD) rats were irradiated with 2 gray once a week for 5 weeks. Bone marrow cells harvested from two male 17-week-old green fluorescence protein-transfected SD rats were placed in primary culture for 7 days. Bone marrow cell-derived outgrowths were harvested by enzymatic digestion and transferred into the atelocollagen-coated temperature-responsive culture dishes for 2 days. To harvest the secondarily cultured cells as monolayer sheets, a support membrane was put in each culture dish, and then the temperature was reduced to 20°C. Each released cell sheet was then patched onto the irradiated anterior bladder wall (n=10). As controls, cell-free sheets were similarly patched (n=10). After 4 weeks, transplanted cells were detected on the bladder walls. The cell sheet-transplanted bladders had smooth muscle layers and acetylcholinesterase-positive nerve fibers in proportions that were significantly larger than those of the control bladders. In addition, the cell sheet-transplanted bladders had reduced prolyl 4-hydroxylase beta (P4HB)-positive regions of collagen synthesis and apoptosis within the smooth muscle layers. In cystometric investigations, threshold pressures, voiding interval, micturition volume, and bladder capacity in the cell sheet-transplantation group were significantly higher than those in the control group. Residual volume of the cell sheet-transplantation group was significantly lower compared with the control. There were 24 growth factor mRNAs in the cell sheet-transplanted urinary bladders that were expressed greater than or equal to two-fold over the controls. In conclusion, cell sheet engineering has great potential to restore damaged urinary bladders.

Alpha1 -adrenergic receptors mediate bladder overactivity induced by cold stress in rats with bladder outlet obstruction.

PURPOSE: To determine if alpha1 -adrenergic receptors (AR) mediate bladder overactivity induced by cold stress in rats with bladder outlet obstruction (BOO). MATERIALS AND METHODS: The urethras of 10-week-old female Sprague-Dawley rats were ligated to create BOO. After 4 weeks, cystometric investigations were performed at room temperature (RT, 27 ± 2°C) for 20 min. The rats were then given 0.3 mg/kg naftopidil (n = 6) or vehicle (n = 5) intravenously. Five minutes later, they were transferred to low temperature (LT, 4 ± 2°C), and the cystometric patterns were again recorded for 40 min. In BOO rats and in sham-operated rats (n = 8) the expression levels of alpha1A - and alpha1D -AR mRNAs and the presence of alpha1A - and alpha1D -AR immunoreactivity on calcitonin gene-related peptide (CGRP)-positive nerve cells were investigated. RESULTS: During LT exposure, the vehicle-treated BOO rats exhibited cold stress-induced bladder overactivity. In the naftopidil-treated rats, the increase of basal pressure and decreases of both voiding interval and bladder capacity induced by LT were significantly reduced compared to the vehicle-treated animals. In the bladders of BOO rats exposed to LT, the expression of alpha1D -AR mRNA was significantly higher than in sham-operated rats, and the immunoreactivity for alpha1D -ARs on the CGRP-positive nerve cells tended to be more pronounced. CONCLUSIONS: Alpha1 -ARs mediate part of the bladder overactivity induced by cold stress in rats with BOO. Cold stress increases the expression of alpha1D -AR mRNA and the immunoreactivity for alpha1D -ARs on the CGRP-positive nerve cells in BOO rats. Naftopidil partially inhibits the cold stress overactivity, suggesting that it is mediated, at least partially, through alpha1D/1A -ARs.

Muscarinic receptors mediate cold stress-induced detrusor overactivity in type 2 diabetes mellitus rats.

OBJECTIVES: This study determined if muscarinic receptors could mediate the cold stress-induced detrusor overactivity induced in type 2 diabetes mellitus rats. METHODS: Ten-week-old female Goto-Kakizaki diabetic rats (n = 12) and Wister Kyoto non-diabetic rats (n = 12) were maintained on a high-fat diet for 4 weeks. Cystometric investigations of the unanesthetized rats were carried out at room temperature (27 ± 2°C) for 20 min. They were intravenously administered imidafenacin (0.3 mg/kg, n = 6) or vehicle (n = 6). After 5 min, the rats were transferred to a low temperature (4 ± 2°C) for 40 min where the cystometry was continued. The rats were then returned to room temperature for the final cystometric measurements. Afterwards, expressions of bladder muscarinic receptor M3 and M2 messenger ribonucleic acids and proteins were assessed by reverse transcription polymerase chain reaction and immunohistochemistry. RESULTS: In non-diabetic Wister Kyoto rats, imidafenacin did not reduce cold stress-induced detrusor overactivity. In diabetic Goto-Kakizaki rats, just after transfer to a low temperature, the cold stress-induced detrusor overactivity in imidafenacin-treated rats was reduced compared with vehicle-treated rats. Within the urinary bladders, the ratio of M3 to M2 receptor messenger ribonucleic acid in the diabetic Goto-Kakizaki rats was significantly higher than that of the non-diabetic Wister Kyoto rats. The proportion of muscarinic M3 receptor-positive area within the detrusor in diabetic Goto-Kakizaki rats was also significantly higher than that in non-diabetic Wister Kyoto rats. CONCLUSIONS: Imidafenacin partially inhibits cold stress-induced detrusor overactivity in diabetic Goto-Kakizaki rats. In this animal model, muscarinic M3 receptors partially mediate cold stress-induced detrusor overactivity.

Implantation of autologous adipose-derived cells reconstructs functional urethral sphincters in rabbit cryoinjured urethra.

We investigated the ability of autologous adipose-derived cells injected into cryoinjured rabbit urethras to improve urinary continence and explored the possible mechanisms by which it occurred. Adipose tissue was harvested from the perivesical region of nine 10-week-old female New Zealand White rabbits and cultured for 7 days. Immediately after harvesting the tissue, we injured the internal urethral orifice by spraying liquid nitrogen for 20 s. The cultured cells expressed the mesenchymal cell marker STRO1, but not muscle cell markers myoglobin or smooth muscle actin (SMA). Just before implantation, the adipose-derived cells were labeled with the PKH26 fluorescent cell linker. Autologous 2.0×10(6) adipose-derived cells (five rabbits) or a cell-free control solution (four rabbits) was injected around the cryoinjured urethras at 7 days after injury. Fourteen days later, the leak point pressure (LPP) was measured, and the urethras were harvested for immunohistochemical analyses. At 14 days after implantation, LPP of the cell-implanted group was significantly higher compared with the cell-free control group (p<0.05). In immunohistochemical examination, the reconstructed skeletal and smooth muscle areas in the cell-implanted regions were significantly more developed than those in controls (p<0.01). Implanted PKH26-labeled adipose-derived cells were immunohistochemically positive for myoglobin, SMA, and Pax7 antibodies, which are markers for skeletal muscles, smooth muscles, and myoblast progenitor cells, respectively. In addition, these implanted cells were positive for the nerve cell markers, tubulin ß3, S100, and the vascular endothelial cell marker, von Willebrand factor. Furthermore, some of the implanted cells were positive for the transforming growth factor ß1, nerve growth factor, and vascular endothelial growth factor. In conclusion, implantation of autologous adipose-derived cells into the cryoinjured rabbit urethras promoted the recovery of urethral function by myogenic differentiation, neuroregeneration, and neoangiogenesis of the implanted cells and/or the surrounding tissues as well as by bulking effects. Thus, treatment of human radical prostatectomy-related stress urinary incontinence by adipose-derived cell implantation could have significant therapeutic effects.

Cold stress induces lower urinary tract symptoms.

Cold stress as a result of whole-body cooling at low environmental temperatures exacerbates lower urinary tract symptoms, such as urinary urgency, nocturia and residual urine. We established a model system using healthy conscious rats to explore the mechanisms of cold stress-induced detrusor overactivity. In this review, we summarize the basic findings shown by this model. Rats that were quickly transferred from room temperature (27 ± 2°C) to low temperature (4 ± 2°C) showed detrusor overactivity including increased basal pressure and decreased voiding interval, micturition volume, and bladder capacity. The cold stress-induced detrusor overactivity is mediated through a resiniferatoxin-sensitve C-fiber sensory nerve pathway involving α1-adrenergic receptors. Transient receptor potential melastatin 8 channels, which are sensitive to thermal changes below 25-28°C, also play an important role in mediating the cold stress responses. Additionally, the sympathetic nervous system is associated with transient hypertension and decreases of skin surface temperature that are closely correlated with the detrusor overactivity. With this cold stress model, we showed that α1-adrenergic receptor antagonists have the potential to treat cold stress-exacerbated lower urinary tract symptoms. In addition, we showed that traditional Japanese herbal mixtures composed of Hachimijiogan act, in part, by increasing skin temperature and reducing the number of cold sensitive transient receptor potential melastatin channels in the skin. The effects of herbal mixtures have the potential to treat and/or prevent the exacerbation of lower urinary tract symptoms by providing resistance to the cold stress responses. Our model provides new opportunities for utilizing animal disease models with altered lower urinary tract functions to explore the effects of novel therapeutic drugs.

A galenical produced from Ba-Wei-Die-Huang-Wan (THC-002) provides resistance to the cold stress-induced detrusor overactivity in conscious rats.

AIMS: We determined if THC-002, a galenical produced from Ba-Wei-Die-Huang-Wan, could increase skin temperature and inhibit detrusor overactivity induced by sudden whole body cooling. Further, we determined if THC-002 could decrease expression of transient receptor potential melastatin 8 (TRPM8) channels associated with the cold responses. METHODS: Hind leg skin temperature of female 10-week-old Sprague-Dawley rats was measured by thermal imaging. Experimental rats (n = 12) were given oral 100 mg/kg THC-002 daily for one week, and controls (n = 12) were similarly treated with THC-002-free solution. Afterwards, thermal imaging and cystometric investigations of the freely moving conscious rats were performed at room temperature (RT, 27 ± 2°C) for 20 min. The rats were then transferred to a low temperature (LT, 4 ± 2°C) environment during which thermal imaging and cystometric measurements were taken at 5, 10, 20, 30, and 40 min. Afterward, the skin tissues were harvested to estimate expression levels of TRPM8 channels by immunohistochemistry and real-time reverse-transcription polymerase chain reaction. RESULTS: The RT skin temperature of THC-002-treated rats was significantly higher than controls. During the first 20 min under LT, the control rats exhibited cold stress-induced detrusor overactivity such as decreased voiding interval and bladder capacity. THC-002 partially inhibited the detrusor overactivity patterns. During the second 20 min, skin temperature was relatively stable, and the detrusor overactivity of both groups slowly disappeared. THC-002 significantly reduced expression of TRPM8 channel protein and mRNA. CONCLUSIONS: THC-002 inhibited cold stress-induced detrusor overactivity resulting from decreasing skin temperature. Therefore, THC-002 might provide resistance to cold stress-exacerbated lower urinary tract symptoms.