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Objective: To examine the effects of the selective 5‐HT1A receptor agonist, NLX‐112, on urethral function in streptozotocin‐induced diabetic rats. Materials and Methods: Female Sprague–Dawley rats (n = 32) were divided into two groups: rats with type 1 diabetes mellitus (T1DM) and age‐matched normal control rats (NC). T1DM was induced by intraperitoneal injection of streptozotocin (65 mg/kg). Isovolumetric cystometry and urethral perfusion pressure (UPP) were evaluated 10 weeks postinjection in rats (n = 9 per group). The selective 5‐HT1A receptor antagonist, WAY‐100635 maleate salt, was administered after NLX‐112 hydrochloride dose–response curve was generated (intravenously). The remaining rats were used for immunofluorescence and Western blot assays. Results: Compared to controls, type 1 diabetic rats (T1D rats) had lower maximal intravesical pressure (IP max) and UPP changes. In T1D rats, NLX‐112 hydrochloride (0.003–1.0 mg/kg) induced dose‐dependent decreases in UPP nadir, IP max, high‐frequency oscillations (HFOs) rate; and increases in UPP change and HFOs amplitude. WAY‐100635 maleate salt (0.3 mg/kg) partially or completely reversed the NLX‐112‐induced changes. Immunofluorescence revealed that 5‐HT1A receptors were found in the L6‐S1 spinal cord dorsolateral nucleus, but the expression was significantly higher in the T1D rats. Additionally, Western blot showed there were significantly more 5‐HT1A receptors in the ventral L6‐S1 spinal cord of T1D rats. Conclusions: Urethral dysfunction in T1D rats was improved by NLX‐112. 5‐HT1A receptors were upregulated in the dorsolateral nucleus of L6‐S1 spinal cord in T1D rats. These findings suggest that NLX‐112 may constitute a novel therapeutic strategy to treat diabetic urethral dysfunction. [ABSTRACT FROM AUTHOR]

We recently demonstrated that treatment with the 5-H[T.sub.1A/7] receptor agonist [(R)-(+)-8-hydroxy-2-di-n-propylamino]tetralin (8-OH-DPAT) increases bladder capacity in chloralose-anesthetized female cats with chronic spinal cord injury. In the current study, we investigated the effects of 8-OH-DPAT on bladder capacity and external urethral sphincter (EUS) activity in urethane-anesthetized female rats (initial body mass 175-200 g) with chronic spinal cord injury (transsection at T10). Cystometric study took place 8-12 wk posttranssection. Intravesical pressure was monitored in urethane-anesthetized rats with a transvesical catheter, and EUS activity was assessed electromyographically. Spinal cord injury disrupts phasic activity of the EUS, resulting in decreased voiding efficiency and increased residual volume. 8-OH-DPAT induced a dose-dependent decrease in bladder capacity (the opposite of its effect in chronic spinal cord-injured cats) with an increase in micturition volume and decrease in residual volume resulting from improvement in voiding efficiency. The unexpected improvement in voiding efficiency can be explained by the 8-OH-DPAT-induced emergence of phasic EUS relaxation. Phasic EUS relaxation was also altered by 8-OH-DPAT in spinally intact rats, whereas the 5-H[T.sub.1A] receptor antagonist N-tert-butyl-3-[4-(2-methoxyphenyl)-piperazin-1-yl]-2-phenylpropanamide (WAY-100635), on its own, was without effect. It remains to be determined when phasic relaxation is restored after spinal cord injury, and indeed whether it is ever truly lost or is only temporarily separated from excitatory input. bladder; micturition; neurogenic voiding; detrusor; urethra

Objectives: To examine the effect of intrathecal (i.t.) serotonin (5‐hydroxytryptamine) 5‐HT7 agonist administration on voiding function in the urethane‐anesthetised rat, and the change in 5‐HT7 receptor (5‐HT7R) expression in the lumbosacral cord Onuf's nucleus after spinal cord injury (SCI). Materials and methods: In all, 32 female Sprague–Dawley (SD) rats were equally divided into a spinally intact (SI) group and SCI group (n = 16 each). At 8 weeks after transection, half of the rats underwent continuous cystometry under urethane anaesthesia, and the 5‐HT7R‐selective agonist LP44 was given (i.t.). The remaining rats were used for pseudorabies (PRV) retrograde tracing, immunofluorescence, and Western Blot. Results: LP44 administered i.t. had no effect in the SI rats. In SCI rats, LP44 (1–30 μg/kg) induced significant dose‐dependent increases in micturition volume, voiding efficiency, number of high‐frequency oscillations per micturition; and decreases in residual volume, bladder capacity, peak bladder pressure, threshold pressure and non‐voiding contractions. The 5‐HT7R antagonist, SB‐269970 (10 μg/kg), partially reversed LP44‐induced changes. Using PRV retrograde tracing and immunofluorescence, 5‐HT7Rs were found in the L6–S1 spinal cord Onuf's nucleus in both SI and SCI rats, but the expression was significantly greater in the SCI rats. Western blot showed significantly more 5‐HT7Rs in the ventral L6–S1 spinal cord in SCI rats. Conclusion: A 5‐HT7R agonist, given i.t., improved voiding efficiency in urethane‐anesthetised SCI rats, and the 5‐HT7R was significantly up‐regulated in the lumbosacral cord Onuf's nucleus. If valid for humans, these findings suggest that the 5‐HT7R could be a target for therapeutic interventions. [ABSTRACT FROM AUTHOR]

Aim: To investigate the value of repeat botulinum toxin A (BTX‐A) injections in patients with neurogenic detrusor overactivity (NDO). Methods: We searched the PubMed, EMBASE, and EBSCO databases for articles published until June 2016. Studies that reported the efficacy and safety of repeat BTX‐A injections for adult patients with NDO were eligible. The effect size for each outcome was calculated as the standardized mean difference ± standard error and 95% confidence interval, and was graded as small, >0.2; moderate, >0.5; or large, >0.8. The outcomes included maximum cystometric capacity (MCC), maximum detrusor pressure (MDP), reflex volume (RV), bladder compliance (BC), quality of life (QOL), and injection interval. Descriptive reviews were performed for urinary incontinence (UI) and adverse events (AEs). Results: Eighteen studies involving 1533 patients whose level of evidence ranged from 3 to 4 were included in this study. We noted non‐significant changes in MCC, MDP, RV, and BC between the first and last injections. Patients who had received ≤4 injections were found to have stable QOL improvements after the first and last injections, whereas patients who had received ≥5 injections were found to have a significant decrease in QOL after the last injection. No significant differences in injection intervals were noted after repeat BTX‐A injections, and the repeat injection failure rate was low. Conclusion: Our study demonstrated that repeat BTX‐A injections allow sustained improvements in patients with NDO. The rate of AEs was stable and low. However, additional high‐quality, large‐scale, and long‐term trials are necessary to establish the efficacy and safety of ≥5 repeat BTX‐A injections. [ABSTRACT FROM AUTHOR]

Objectives: To investigate whether the voiding dysfunction caused by spinal cord injury (SCI) in rats can be improved by i.v. administration of the serotonin (5‐HT)2A/2C receptor agonist 2,5‐dimethoxy‐4‐iodophenyl‐2‐aminopropanehydrochloride (DOI), and to discuss whether the mechanism can be ascribed to 5‐HT2A and 5‐HT 2C receptor upregulation in lumbosacral cord motoneurons. Materials and Methods: Female Sprague–Dawley rats were divided into two groups (SCI group vs normal control [NC] group). Under urethane anaesthesia, cystometry was performed to examine the variation in urodynamic variables before and after successive intrathecal (i.t.) administration of various doses of DOI into the lumbosacral cord. Changes in 5‐HT2A and ‐2C receptors in the lumbosacral cord were also investigated using immunohistochemical staining and Western blot analysis. Results: Compared with NC rats, the SCI rats had higher bladder capacity and post‐void residual urine volume, and lower voiding efficiency. After SCI, DOI improved voiding efficiency, probably via external urethral sphincter (EUS) activity. Immunohistochemical staining and Western blot analysis showed that 5‐HT2A and ‐2C receptors were upregulated in lumbosacral cord motoneurons. Conclusion: In rats with SCI, DOI can improve voiding efficiency; this may be attributable to 5‐HT2A and ‐2C receptor upregulation in lumbosacral cord motoneurons controlling EUS activity. [ABSTRACT FROM AUTHOR]

Purpose: The study aimed to evaluate the effects of metformin on insulin, C-peptide and body weight in Chinese men undergoing androgen deprivation therapy (ADT). Methods: Between March 2013 and June 2014, 62 newly diagnosed patients of prostate cancer (PCa) due to receive ADT were recruited from 7 hospitals in Shanghai. Patients were randomized to respectively receive ADT (n = 31) and ADT + metformin (n = 31) for 6 months. Fasting and postprandial serum levels of insulin and C-peptide, blood glucose, prostate specific antigen, body mass index (BMI) and waist circumference (WC) were measured at the beginning and end of 6-month treatment. Results: Baseline characteristics were comparable between the 2 groups. Controlling for baseline levels, the ADT group had significantly higher levels of fasting glucose (p = 0.01) and higher WC (p = 0.04) than the ADT + metformin group. The levels of insulin, C-peptide and BMI did not differ significantly. Conclusions: Metformin may be potentially efficient as a concomitant therapy on patients with PCa undergoing androgen deprivation treatment. [ABSTRACT FROM AUTHOR]