Intradetrusor OnabotulinumtoxinA Injections Ameliorate Autonomic Dysreflexia while Improving Lower Urinary Tract Function and Urinary Incontinence-Related Quality of Life in Individuals with Cervical and Upper Thoracic Spinal Cord Injury.

Pilot data of our phase IV clinical trial (pre/post study design) highlighted a beneficial effect of intradetrusor onabotulinumtoxinA (200 IU) injections to reduce autonomic dysreflexia (AD) in individuals with chronic spinal cord injury (SCI) at T6 or above. After trial completion, we assessed whether our primary expectation (i.e., decrease of AD severity in 50% of participants during urodynamics [UDS]) was met. Secondary outcome measures were reduction of spontaneous AD in daily life as well as amelioration of AD-related and urinary incontinence-related quality of life (QoL). In addition, we conducted injury-level-dependent analysis-i.e., cervical and upper thoracic-to explore group-specific treatment efficacy. Post-treatment, AD severity decreased in 82% (28/34) of all participants during UDS and in 74% (25/34) in daily life assessed with 24-h ambulatory blood pressure monitoring. In addition, urinary incontinence-related QoL was improved, cystometric capacity was increased, and maximum detrusor pressure during storage was reduced (all p < 0.001). Further, the treatment was well tolerated, with only minor complications (grade I [n = 7] and II [n = 7]) in accordance with the Clavien-Dindo classification recorded in 11 individuals (cervical n = 9, upper thoracic n = 2). Injury-level-dependent analysis revealed lower incidence (cervical n = 15/23, upper thoracic n = 6/11) and lesser severity (cervical p = 0.009; upper thoracic p = 0.06 [Pearson r = -0.6, i.e., large effect size]) of AD during UDS. Further, reduced AD severity in daily life, improved urinary incontinence-related QoL, greater cystometric capacity, and lower maximum detrusor pressure during storage (all p < 0.05) were found in both groups post-treatment. Intradetrusor onabotulinumtoxinA injections are an effective and safe second-line treatment option that ameliorates AD while improving lower urinary tract function and urinary incontinence-related QoL in individuals with cervical and upper thoracic SCI.

Impact of sex, androgens, and prostate size on C57BL/6J mouse urinary physiology: functional assessment.

Laboratory mice are used to identify causes of urinary dysfunction including prostate-related mechanisms of lower urinary tract symptoms. Effective use of mice for this purpose requires a clear understanding of molecular, cellular, anatomic, and endocrine contributions to voiding function. Whether the prostate influences baseline voiding function has not been specifically evaluated, in part because most methods that alter prostate mass also change circulating testosterone concentrations. We performed void spot assay and cystometry to establish a multiparameter "baseline" of voiding function in intact male and female 9-wk-old (adult) C57BL/6J mice. We then compared voiding function in intact male mice to that of castrated male mice, male (and female) mice treated with the steroid 5α-reductase inhibitor finasteride, or male mice harboring alleles (Pbsn4cre/+; R26RDta/+) that significantly reduce prostate lobe mass by depleting prostatic luminal epithelial cells. We evaluated aging-related changes in male urinary voiding. We also treated intact male, castrate male, and female mice with exogenous testosterone to determine the influence of androgen on voiding function. The three methods used to reduce prostate mass (castration, finasteride, and Pbsn4cre/+; R26RDta/+) changed voiding function from baseline but in a nonuniform manner. Castration feminized some aspects of male urinary physiology (making them more like intact female mice) while exogenous testosterone masculinized some aspects of female urinary physiology (making them more like intact male mice). Our results provide evidence that circulating testosterone is responsible in part for baseline sex differences in C57BL/6J mouse voiding function while prostate lobe mass in young, healthy adult mice has a lesser influence.

Effect of orchiectomy and testosterone replacement on lower urinary tract function in anesthetized rats.

Lower urinary tract (LUT) symptoms (LUTS), including frequency, urgency, incomplete voiding, and slow stream, are common in both men and women with advancing age. The most common cause for LUTS in aging men is benign prostatic hyperplasia. Some studies have also revealed an inverse association of serum testosterone levels with LUTS; however, the underlying mechanisms by which gonadal hormones affect the LUT have not been clarified. In the present study, we examined the effect of orchiectomy and testosterone replacement on LUT function in adult male Sprague-Dawley rats. Six weeks after bilateral orchiectomy or sham operations and 3 wk after injection of long-acting testosterone undecanoate (100 mg/kg im), transvesical cystometry and external urethral sphincter electromyogram (EUS EMG) recordings were performed under urethane anesthesia. The micturition reflex was elicited in both sham and orchiectomized animals. In orchiectomized rats, volume threshold for inducing micturition decreased by 47.6%; however, contraction amplitude, duration, and voiding efficiency were similar in sham and orchiectomized rats. The active period during EUS EMG bursting was lengthened during micturition in orchiectomized animals. Testosterone treatment, which normalized plasma testosterone levels, reversed these changes but also increased the duration of EUS EMG bursting. Orchiectomy also reduced mean voiding flow rate estimated from the duration of EUS EMG bursting, an effect that was not reversed by testosterone. The results indicate that orchiectomy affects both the active and passive properties of the bladder and urethra, and that many, but not all, of the changes can be reversed by testosterone.

Impact of a folic acid-enriched diet on urinary tract function in mice treated with testosterone and estradiol.

Aging men are susceptible to developing lower urinary tract symptoms, but the underlying etiology is unknown and the influence of dietary and environmental factors on them is unclear. We tested whether a folic acid-enriched diet changed urinary tract physiology and biology in control male mice and male mice with urinary dysfunction induced by exogenous testosterone and estradiol (T+E2), which mimics changing hormone levels in aging humans. T+E2 treatment increased mouse urine output, time between voiding events, and bladder capacity and compliance. Consumption of a folic acid-enriched diet moderated these changes without decreasing prostate wet weight or threshold voiding pressure. One potential mechanism for these changes involves water balance. T+E2 treatment increases plasma concentrations of anti-diuretic hormone, which is offset at least in part by a folic acid-enriched diet. Another potential mechanism involves neural control of micturition. The folic acid-enriched diet, fed to T+E2-treated mice, increased voiding frequency in response to intravesicular capsaicin infusion and increased mRNA abundance of the capsaicin-sensitive cation channel transient receptor potential vanilloid subfamily member 1 (Trpv1) in L6 and S1 dorsal root ganglia (DRG) neurons. T+E2 treatment and a folic acid-enriched diet also modified DNA methylation, which is capable of altering gene expression. We found the enriched diet increased global DNA methylation in dorsal and ventral prostate and L6 and S1 DRG. Our results are consistent with folic acid acting to slow or reverse T+E2-mediated alteration in urinary function in part by normalizing water balance and enhancing or preserving afferent neuronal function.

Quercetin regulates organic ion transporter and uromodulin expression and improves renal function in hyperuricemic mice.

BACKGROUND: Renal organic ion transporters and uromodulin (UMOD) play the important roles in renal urate excretion and function. Hyperuricemia is considered as a risk factor for the development of renal dysfunction. The flavonoid quercetin in diets exerts the hypouricemic and nephroprotective effects. PURPOSES: To evaluate the effects of quercetin on renal organic ion transporters and UMOD in hyperuricemic mice. METHODS: Kun-Ming mice were divided into normal and hyperuricemic groups receiving water, 25, 50 and 100 mg/kg quercetin, 5 mg/kg allopurinol, respectively. Hyperuricemic mice were orally gavaged with 250 mg/kg oxonate daily for 1 week. Quercetin and allopurinol were orally gavaged on the day when oxonate or water was given 1 h later. After 1 week, serum uric acid, creatinine and blood urea nitrogen concentrations, excretion of urate and creatinine, and fractional excretion of uric acid were measured. The mRNA and protein levels of renal urate transporter 1 (mURAT1), glucose transporter 9 (mGLUT9), organic anion transporter 1 (mOAT1) and organic cation/carnitine transporters (mOCT1, mOCT2, mOCTN1 and mOCTN2) in mice were analyzed. Simultaneously, UMOD levels in serum, urine and kidney, as well as renal UMOD mRNA expression were detected. RESULTS: Quercetin significantly restored oxonate-induced abnormalities of these biochemical indexes compared with normal vehicle group. Furthermore, it remarkably prevented expression changes of renal organic ion transporters and UMOD, and UMOD level alteration in hyperuricemic mice. CONCLUSIONS: These results suggest that quercetin has the uricosuric and nephroprotective actions mediated by regulating the expression levels of renal organic ion transporters and UMOD.

Molecular and pharmacological detection of dopaminergic receptors in the human male urinary tract.

AIMS: Evidence indicates that dopamine (DA) and DA receptors play a role in the central nervous system (CNS) control of micturition; however, while the central DAergic role in the micturition physiology has been extensively investigated, the expression and the function of DA receptors in the urinary tract are still under investigation. Here, we studied the distribution of DA receptor subtypes in different parts of the human male urinary tract. METHODS: Fragments were collected from 34 men. The mRNAs encoding DA receptors were assessed by RT-PCR, followed by densitometric analysis. Adenylyl cyclase (AC) activity was evaluated using a commercially available RIA kit. Statistical analysis was carried out using one-way ANOVA, with the Bonferroni's post hoc test. RESULTS: Results obtained indicated that RT-PCR products of D(1), D(4), and D(5) subtypes were obtained in each part studied, while no signal was observed for the D(2) and D(3) receptor subtypes. The pharmacological characterization demonstrated that the expressed DA receptors were linked to AC. CONCLUSIONS: DA receptors were expressed throughout the human male urinary tract, from the ureter to the prostatic urethra. In particular, we observed a distinctive DA receptor subtype distribution, with evidence of the presence of mRNA encoding both subtypes of the D(1)-like DA receptor family (D(1) and D(5)), while the D(4) receptors were the only expressed subtype of the D(2)-like family. These results suggested that DAergic drugs used for the treatment of a number of diseases may influence the micturition physiology not only in the CNS, but at the peripheral level as well.

Effect of lumbar-epidural administration of tramadol on lower urinary tract function.

AIMS: Intrathecal and epidural administration of micro-agonist opioids is associated with urinary retention, a potentially serious adverse-event. In animal studies tramadol has been found not to affect voiding function. We evaluated urodynamic effects of epidural tramadol in humans. METHODS: Fifteen adults planned for cystoscopy under local-anesthesia underwent urodynamics (UDS) at baseline and 30 min after administration of 100 mg tramadol in lumbar-epidural space. UDS consisted of filling cystometry, pressure-flow study and pelvic floor electromyography (EMG). Subsequently, all underwent cystoscopy and were observed for 6 hr. RESULTS: After injection of tramadol, a significant rise was observed in bladder capacity (391.8 +/- 179.6 ml vs. 432.7 +/- 208.8 ml; P = 0.019) and compliance (60.1 +/- 51.5 ml/cm H(2)O vs. 83.0 +/- 63.0 ml/cm H(2)O; P = 0.011) without a significant change in filling pressure (22.5 +/- 13.2 cm H(2)O vs. 24.1 +/- 15.1 cm H(2)O; P = 0.576). Filling sensations were delayed significantly (P < or = 0.05). EMG during filling phase showed a significant fall (P = 0.027). Peak flow-rate (Q(max)), average flow-rate, postvoid residue and detrusor pressure-at-Q(max) did not show significant change from baseline (P > 0.05). Three patients had bladder outlet obstruction which did not worsen after the injection. Guarding reflex was inhibited in seven out of 12 patients who had it at baseline (P = 0.016). CONCLUSIONS: Epidural tramadol increases the bladder capacity and compliance and delays filling-sensations, without ill effect on voiding. This seems true even for patients with obstructed outflow; however, due to small number of patients a definite conclusion cannot be derived. These results will guide clinician to avoid catheterization in cases where epidural tramadol is used for postoperative pain. The inhibitory effects of tramadol on EMG activity are intriguing and need further studies.

Beneficial effect of aspirin on renal function post-cardiopulmonary bypass.

Urine thromboxane, plasma creatinine, and creatinine clearance were determined perioperatively in 20 patients undergoing coronary bypass surgery. Ten patients took aspirin until the day of surgery, and 10 discontinued aspirin at least one week before surgery. A significant increase in urine thromboxane following establishment of cardiopulmonary bypass was observed only in the control group. Plasma creatinine increased in the control group on the 1st postoperative day (from 81.9 +/- 13.2 to 97.6 +/- 13.2 micromol.L(-1), p = 0.02) and decreased next day to the preoperative level (82.7 +/- 9 micromol.L(-1), p = 0.03). In the aspirin group, creatinine remained unchanged on the 1st postoperative day (89.4 +/- 14.2 vs. 87.2 +/- 7.7 micromol.L(-1), p = 0.6), and increased significantly on the 2nd day (101.4 +/- 8.5 micromol.L(-1), p = 0.01). The aspirin group had higher creatinine levels (p < 0.0001) and lower creatinine clearance (60.2 +/- 16.5 vs. 82 +/- 25.7 mL.min(-1), p < 0.0001) than the control group on the 2nd postoperative day. A significant positive correlation was seen between urine thromboxane and creatinine on day 2 in both groups (r = 0.6). Aspirin administrated before coronary surgery may have a beneficial effect on renal function, probably mediated by its antiplatelet activity and thromboxane inhibition.

Pharmacologic perspective on the physiology of the lower urinary tract.

Myogenic activity, distention of the detrusor, and signals from the urothelium may initiate voiding. In the bladder, afferent nerves have been identified not only in the detrusor, but also suburothelially, where they form a plexus that lies immediately beneath the epithelial lining. Extracellular adenosine triphosphate (ATP) has been found to mediate excitation of small-diameter sensory neurons via P2X3 receptors, and it has been shown that bladder distention causes release of ATP from the urothelium. In turn, ATP can activate P2X3 receptors on suburothelial afferent nerve terminals to evoke a neural discharge. However, most probably, not only ATP but also a cascade of inhibitory and stimulatory transmitters and mediators are involved in the transduction mechanisms underlying the activation of afferent fibers during bladder filling. These mechanisms may be targets for future drugs. The central nervous control of micturition involves many transmitter systems, which may be suitable targets for pharmacologic intervention. gamma-Aminobutyric acid, dopamine, enkephalin, serotonin, and noradrenaline receptors and mechanisms are known to influence micturition, and potentially, drugs that affect these systems could be developed for clinical use. However, a selective action on the lower urinary tract may be difficult to obtain. Most drugs currently used for treatment of detrusor overactivity have a peripheral site of action, mainly the efferent (cholinergic) neurotransmission and/or the detrusor muscle itself. In the normal bladder, muscarinic receptor stimulation produces the main part of detrusor contraction, but evidence is accumulating that in disease states, such as neurogenic bladders, outflow obstruction, idiopathic detrusor instability, and interstitial cystitis, as well as in the aging bladder, a noncholinergic activation via purinergic receptors may occur. If this component of activation is responsible not only for part of the bladder contractions, but also for the symptoms of the overactive bladder, it should be considered an important target for therapeutic interventions.

KMD-3213, a uroselective and long-acting alpha(1a)-adrenoceptor antagonist, tested in a novel rat model.

KMD-3213, an alpha(1a)-adrenoceptor (AR) antagonist, is under development for the treatment of urinary outlet obstruction in patients with benign prostatic hypertrophy. In the present study, we developed a rat model to investigate simply the effects of alpha(1)-AR antagonists on the intraurethral pressure (IUP) response to phenylephrine. Using this model, inhibitory effects of both i.v. and intraduodenally administered KMD-3213 on the IUP response were evaluated and compared to those of other reference compounds, including prazosin and tamsulosin. In addition, the hypotensive effects of these compounds were estimated to evaluate uroselectivity. Intravenously administered alpha(1)-AR antagonists tested, including KMD-3213, potently inhibited the IUP response in a dose-dependent manner. Although the higher doses of those compounds almost completely inhibited the IUP response, yohimbine failed to inhibit the response. When the in vivo potencies of those compounds on IUP response were correlated with their affinities for the human or animal recombinant alpha(1)-AR subtypes, alpha(1a)-AR gave the best correlation. In this model, KMD-3213 had greater uroselectivity than any other compounds examined, by both i.v. and intraduodenal routes. Moreover, 12, 18, and 24 h after the oral administration of KMD-3213, a dose-dependent inhibition of the IUP response was found, whereas the effect of tamsulosin disappeared at 18 h after the oral administration. These data indicate that KMD-3213 is a highly uroselective alpha(1)-AR antagonist with a longer duration of action. In addition, this model is useful for not only estimation of uroselectivity but also some part of the administration, distribution, metabolism, and excretion of many compounds to discover uroselective compounds.