RESUMO
OBJECTIVE: To characterize the bulbospongiosus muscle (BSM) in patients with bulbar urethral strictures. MATERIALS AND METHODS: We studied 21 patients divided into 2 groups: Stricture Group (nâ¯=â¯14; mean ageâ¯=â¯62.00 years) with bulbar stricture submitted to open urethroplasty; and Control Group (nâ¯=â¯7; mean ageâ¯=â¯60.14 years) with penile strictures (hypospadias cripples, penile cancer and/or penile infection) who were submitted to perineal urethrostomy. Samples of the BSM were dissected and histologic sections were stained by histochemical and immunohistochemical techniques. Histomorphometric analyzes were performed on photomicrographs. Means were statistically compared using the unpaired Student t test and the Mann-Whitney test (P <.05). RESULTS: The etiology of bulbar urethral stricture was idiopathic in 2 cases (14.29%), post-TURP in 6 (42.86%), post open radical prostatectomy in 5 (35.71%) and post open prostatectomy in 1 case (7.14%). The average length of the stricture was 2.08 cm. The only parameter analyzed with significant difference between the groups was the vessels (significant difference between the control group: 5.11 ± 1.98% and stricture group: 3.57 ± 1.32%, Pâ¯=â¯.0460). The quantitative analysis of collagen (Control Group: 10.63 ± 5.37% and Stricture Group: 10.83 ± 4.55%, Pâ¯=â¯.9296); diameter of BSM muscle fibers (Control Group: 41.71 ± 14.63 µm and Stricture Group: 40.11 ± 8.59 µm, Pâ¯=â¯.76 and elastic system fibers (Control Group; 3.83 ± 1.54% and Stricture Group: 5.43 ± 2.90%, Pâ¯=â¯.2601) showed no significant difference. CONCLUSIONS: Histologic analysis showed a significant decrease of the BSM vessels in urethral stricture, without changes in elastic fibers, collagen, nerves, and muscle fiber diameter. These findings show that the bulbar urethral stricture causes minimal alterations in the structure of the BSM.
Assuntos
Doenças do Pênis , Pênis , Complicações Pós-Operatórias , Uretra , Estreitamento Uretral , Procedimentos Cirúrgicos Urológicos , Pesos e Medidas Corporais/métodos , Brasil , Constrição Patológica , Correlação de Dados , Técnicas de Imagem por Elasticidade/métodos , Humanos , Imuno-Histoquímica , Masculino , Pessoa de Meia-Idade , Doenças do Pênis/diagnóstico , Doenças do Pênis/etiologia , Pênis/patologia , Pênis/cirurgia , Complicações Pós-Operatórias/diagnóstico , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/patologia , Procedimentos de Cirurgia Plástica/métodos , Uretra/irrigação sanguínea , Uretra/inervação , Uretra/patologia , Uretra/cirurgia , Estreitamento Uretral/diagnóstico , Estreitamento Uretral/epidemiologia , Estreitamento Uretral/etiologia , Estreitamento Uretral/patologia , Procedimentos Cirúrgicos Urológicos/efeitos adversos , Procedimentos Cirúrgicos Urológicos/métodosRESUMO
AIMS: The objective of this study was to evaluate the similarities and differences of the urethral morphological and functional changes following external urethral sphincter EUS injury in male and female rats. METHODS: 30 female and 30 male age-matched Wistar rats were used in the experiments. Half of them underwent electrocauterization of the surrounding tissues lateral to the urethra at the level of the (EUS) and the others, a sham operation. At 2, 6, and 16 weeks after surgeries they underwent anesthetized cystometry, measurement of leak point pressure (LPP) and their urethras were harvested for morphological analyses. RESULTS: There were no differences in cystometric parameters between sex-time-matched animals, ensuring normal bladder function in the manipulated animals. The mean LPP in male and female rats was lower compared with sham animals. Age-time-matched sham operated male rats exhibited a higher LPP compared with female rats. The reduction in LPP comparing electrocauterized and sham time-matched animals was more pronounced in male rats than in female rats. Electrocauterization produced urethral collagen deposition and nerve damage in both male and female animals. Muscle atrophy and disruption also occurred, being more evident in female rats. CONCLUSIONS: The urethras of male and female rats exhibited a similar morphological and functional response to electrocauterization. The time-course evaluation revealed that the male animal model is as reliable, reproducible and long-lasting as the female model. Intact males had a higher LPP than female rats and the nerve injury led to a more drastic impairment of this mechanism.
Assuntos
Uretra/lesões , Incontinência Urinária por Estresse/etiologia , Animais , Colágeno/metabolismo , Modelos Animais de Doenças , Eletrocoagulação , Feminino , Fibrose , Masculino , Atrofia Muscular/etiologia , Atrofia Muscular/patologia , Atrofia Muscular/fisiopatologia , Regeneração Nervosa , Traumatismos dos Nervos Periféricos/etiologia , Traumatismos dos Nervos Periféricos/patologia , Traumatismos dos Nervos Periféricos/fisiopatologia , Pressão , Ratos Wistar , Fatores Sexuais , Fatores de Tempo , Uretra/inervação , Uretra/metabolismo , Uretra/fisiopatologia , Incontinência Urinária por Estresse/metabolismo , Incontinência Urinária por Estresse/patologia , Incontinência Urinária por Estresse/fisiopatologia , UrodinâmicaRESUMO
INTRODUCTION AND HYPOTHESIS: Although still a matter of debate, stress urinary incontinence (SUI) may be accompanied by damage to urethral and pelvic floor innervations, thus promoting dysfunctions of the urethral support and sphincteric closure mechanisms. The aim of this study was to analyze the pelvic floor and urethral innervations through pelvic electrophysiological tests to identify whether neurological alterations interfere with urinary continence and urethral functional activity. METHODS: This prospective study included 52 women, 33 with clinically and urodynamically proven SUI and 19 continent volunteers matched for age, height, parity, and number of vaginal deliveries by the propensity score method. The patients were divided according to the severity of urinary loss evaluated by measuring abdominal leak point pressure (ALPP). Pudendal nerve terminal motor latency (PNTML), pudendal somatosensory evoked potential (SSEP) latencies, urethral and clitoral sensory thresholds, and urethroanal reflex latency were tested. RESULTS: SUI and control subjects did not differ in PNTML, SSEP latency, and clitoral sensory thresholds. However, reduced responsiveness to urethral electrosensitivity and prolonged urethroanal reflex latency were detected in most incontinent patients. In addition, urethral electrosensitivity was altered in suspected intrinsic sphincteric dysfunction. CONCLUSIONS: Urethral afferent pathways can be altered in women with SUI and may play an important role in evoking intrinsic sphincteric dysfunction.
Assuntos
Potenciais Somatossensoriais Evocados , Diafragma da Pelve/inervação , Nervo Pudendo/fisiopatologia , Uretra/inervação , Uretra/fisiopatologia , Incontinência Urinária por Estresse/fisiopatologia , Adulto , Idoso , Feminino , Humanos , Pessoa de Meia-Idade , Limiar SensorialRESUMO
PURPOSE: We evaluated the somatic and autonomic innervation of the pelvic floor and rhabdosphincter before and after nerve sparing radical retropubic prostatectomy using neurophysiological tests and correlated findings with clinical parameters and urinary continence. MATERIALS AND METHODS: From February 2003 to October 2005, 46 patients with prostate cancer were enrolled in a controlled, prospective study. Patients were evaluated before and 6 months after nerve sparing radical retropubic prostatectomy using the UCLA-PCI urinary function domain and neurophysiological tests, including somatosensory evoked potential, and the pudendo-urethral, pudendo-anal and urethro-anal reflexes. Clinical parameters and urinary continence were correlated with afferent and efferent innervation of the membranous urethra and pelvic floor. We used strict criteria to define urinary continence as complete dryness with no leakage at all, not requiring any pads or diapers and with a UCLA-PCI score of 500. Patients with a sporadic drop of leakage, requiring up to 1 pad daily, were defined as having occasional urinary leakage. RESULTS: Two patients were excluded from study due to urethral stricture postoperatively. We evaluated 44 patients within 6 months after surgery. The pudendo-anal and pudendo-urethral reflexes were unchanged postoperatively (p = 0.93 and 0.09, respectively), demonstrating that afferent and efferent pudendal innervation to this pelvic region was not affected by the surgery. Autonomic afferent denervation of the membranous urethral mucosa was found in 34 patients (77.3%), as demonstrated by a postoperative increase in the urethro-anal reflex sensory threshold and urethro-anal reflex latency (p <0.001 and 0.0007, respectively). Six of the 44 patients used pads. One patient with more severe leakage required 3 pads daily and 23 showed urinary leakage, including 5 who needed 1 pad per day and 18 who did not wear pads. Afferent autonomic denervation at the membranous urethral mucosa was found in 91.7% of patients with urinary leakage. Of 10 patients with preserved urethro-anal reflex latency 80% were continent. CONCLUSIONS: Sensory and motor pudendal innervation to this specific pelvic region did not change after nerve sparing radical retropubic prostatectomy. Significant autonomic afferent denervation of the membranous urethral mucosa was present in most patients postoperatively. Impaired membranous urethral sensitivity seemed to be associated with urinary incontinence, particularly in patients with occasional urinary leakage. Damage to the afferent autonomic innervation may have a role in the continence mechanism after nerve sparing radical retropubic prostatectomy.
Assuntos
Neurônios Aferentes/fisiologia , Prostatectomia/efeitos adversos , Prostatectomia/métodos , Uretra/inervação , Incontinência Urinária/etiologia , Incontinência Urinária/prevenção & controle , Adulto , Idoso , Humanos , Masculino , Pessoa de Meia-Idade , Estudos ProspectivosRESUMO
OBJECTIVE: To describe the arrangement of the muscle fibers of the striated urethral sphincter and its relationship with the prostate during the fetal period in humans. MATERIALS AND METHODS: We analyzed 17 prostates from well preserved fresh human fetuses ranging in age from 10 to 31 weeks postconception (WPC). Transversal sections were obtained and stained with Gomori's trichrome and immunolabeled with anti alpha-actin antibody. RESULTS: We found that the urethral striated sphincter (rabdosphincter) is located on the periphery of the smooth muscle and there was no merge between striated and smooth muscle fibers in any fetal period. In the prostate apex, the striated sphincter shows a circular arrangement and covers completely the urethra externally, whereas adjacent to verumontanum, it looks like a "horseshoe" and covers only the anterior and lateral surfaces of the urethra. Near the bladder neck, in fetuses younger than 20 WPC, we have found striated muscle fibers only at the anterior surface of the prostate, while in fetuses older than 20 WPC, the striated muscle covers the anterior and lateral surfaces of the prostate. CONCLUSIONS: The urethral sphincter muscle covers the anterior and lateral surfaces of the urethra in all fetuses older than 20 WPC, close to the bladder neck and at the distal prostate. In the region of the prostate apex, the urethral sphincter covers completely the urethra circularly. The knowledge of the normal anatomy of the urethral sphincter in fetuses could be important to understand its alterations in congenital anomalies involving the base of the bladder, the bladder neck and the proximal urethra.
Assuntos
Feto , Fibras Musculares Esqueléticas/citologia , Músculo Esquelético/citologia , Próstata/anatomia & histologia , Uretra/inervação , Humanos , Imuno-Histoquímica , Masculino , Músculo Esquelético/inervação , Próstata/embriologia , Uretra/citologia , Uretra/embriologiaRESUMO
OBJECTIVE: To describe the arrangement of the muscle fibers of the striated urethral sphincter and its relationship with the prostate during the fetal period in humans. MATERIALS AND METHODS: We analyzed 17 prostates from well preserved fresh human fetuses ranging in age from 10 to 31 weeks postconception (WPC). Transversal sections were obtained and stained with Gomori's trichrome and immunolabeled with anti alpha-actin antibody. RESULTS: We found that the urethral striated sphincter (rabdosphincter) is located on the periphery of the smooth muscle and there was no merge between striated and smooth muscle fibers in any fetal period. In the prostate apex, the striated sphincter shows a circular arrangement and covers completely the urethra externally, whereas adjacent to verumontanum, it looks like a "horseshoe" and covers only the anterior and lateral surfaces of the urethra. Near the bladder neck, in fetuses younger than 20 WPC, we have found striated muscle fibers only at the anterior surface of the prostate, while in fetuses older than 20 WPC, the striated muscle covers the anterior and lateral surfaces of the prostate. CONCLUSIONS: The urethral sphincter muscle covers the anterior and lateral surfaces of the urethra in all fetuses older than 20 WPC, close to the bladder neck and at the distal prostate. In the region of the prostate apex, the urethral sphincter covers completely the urethra circularly. The knowledge of the normal anatomy of the urethral sphincter in fetuses could be important to understand its alterations in congenital anomalies involving the base of the bladder, the bladder neck and the proximal urethra.
Assuntos
Humanos , Masculino , Feto , Fibras Musculares Esqueléticas , Músculo Esquelético/citologia , Próstata/anatomia & histologia , Uretra/inervação , Imuno-Histoquímica , Músculo Esquelético/inervação , Próstata/embriologia , Uretra/citologia , Uretra/embriologiaRESUMO
This study aims to evaluate the urethral nerve fibers of adult female rats during pregnancy and after vaginal birth, cesarean section or simulated birth trauma. For immunohistochemical analysis of nerve fibers, 70 female rats were distributed in seven groups of ten female rats: group 1, control; group 2, pregnant; group 3, cesarean section; group 4, vaginal birth; group 5, virgin female rats with simulated birth trauma; group 6, cesarean section followed by simulation of birth trauma; and group 7, vaginal birth followed by simulation of birth trauma. The number of nerve fibers in groups 1, 2, and 3 were significantly higher than the other groups. Pregnancy and cesarean section did not cause alterations in the nerve fibers number. Vaginal birth and simulated birth trauma significantly decreased the number of nerve fibers in the female rats' middle urethra.
Assuntos
Fibras Nervosas/fisiologia , Parto , Uretra/inervação , Animais , Feminino , Gravidez , Ratos , Uretra/citologiaRESUMO
AIMS OF STUDY: The sensory evaluation of the lower urinary tract is summarized in the bladder proprioceptive sensitivity during cystometry. Experimental studies suggest that abnormalities of the urethral innervation and micturition reflex can be related to the presence of continence disturbances. This study aimed to measure the urethral sensory threshold and the urethro-anal reflex latency in healthy volunteers, establishing reading criteria, comparing the results and technique used with the literature and verifying the effect of physiological factors. MATERIALS AND METHODS: Thirty healthy female volunteers were studied. They had an absence of genital or urinary complaints and had undergone no previous pelvic or vaginal procedures. The measurement of the urethral sensory threshold and urethro-anal reflex latency were performed as described. RESULTS: The determination of the urethral sensory threshold and urethro-anal reflex latency were obtained in 96.6% of the volunteers. The electrophysiological parameters did not correlate with age, parity or number of vaginal deliveries. There was a positive association of the urethral sensory threshold with height. Technical aspects were considered and compared with those in the literature as well as the advantages and limitations of the method. CONCLUSIONS: The measurement of the urethral sensory threshold and urethro-anal reflex latency presented consistent recordings. The urethral sensory threshold should be analyzed carefully in individuals with height above the population average. Subsequent observations are necessary to clarify their function in patients with continence disturbances and to measure the urethral function, but these values can be used as normal parameters for comparison.
Assuntos
Canal Anal/fisiologia , Reflexo/fisiologia , Limiar Sensorial , Uretra/fisiologia , Adulto , Canal Anal/inervação , Feminino , Humanos , Modelos Lineares , Valores de Referência , Uretra/inervaçãoRESUMO
One of the hypotheses to explain the neural mechanisms underlying rhythmic behaviours suggests that the central nervous system has the intrinsic capacity to produce repetitive, rhythmic output to the muscles involved in the response by means of a neuronal circuit named central pattern generator (CPG). The occurrence of rhythmic motor patterns during ejaculatory behaviour in mammals, which includes the genital motor pattern, has been shown. A CPG might regulate the timing of the repetitive muscular responses that constitute the ejaculatory motor pattern. The objective of the present study was to evidence that a CPG at a spinal level is involved in the expression and pacing of the rhythmic motor pattern generated during ejaculation. To this purpose we used the genital reflex as a model system. Following the general principles for the study of rhythmic motor patterns, the data obtained in the present series of experiments document that: (1) a rhythmic muscular response, the genital motor pattern, is registered during the ejaculatory event (expulsion of the urethral contents); (2) this ejaculatory motor response has similar EMG characteristics in intact and in spinal urethane-anaesthetised male rats; (3) interruption of the afferent inflow (deafferentation) does not disrupt the expression of the ejaculatory motor train; (4) a change in the stimulation interval does not alter the intrinsic pacing of the ejaculatory-like response; and (5) fictive ejaculation can be induced by pharmacological means. Together, this evidence supports the notion that a CPG produces the rhythmic ejaculatory motor pattern registered during fictive ejaculation.
Assuntos
Ejaculação/fisiologia , Genitália Masculina/fisiologia , Medula Espinal/fisiologia , 8-Hidroxi-2-(di-n-propilamino)tetralina/farmacologia , Anestesia , Animais , Copulação/fisiologia , Denervação , Estimulação Elétrica , Eletromiografia , Genitália Masculina/inervação , Masculino , Movimento/fisiologia , Músculo Liso/inervação , Músculo Liso/fisiologia , Ratos , Reflexo/fisiologia , Escroto/inervação , Escroto/fisiologia , Agonistas do Receptor de Serotonina/farmacologia , Uretra/inervação , Uretra/fisiologiaRESUMO
It was evaluated in the spinal cord-transected rats whether the urethrogenital (UG) reflex shows some of the features that are present during ejaculation in intact animals. It was found that the UG reflex was facilitated after its first elicitation: the latency of the reflex was shorter than the previous one and low intensity of stimulation was needed to produce the reflex. In addition, a change in the latency of the reflex was found that was correlated with the number of stimulation trials. The latency change showed a J-shaped curve that is similar to that found for the ejaculation latency in a copulatory series. An inhibition of the reflex appeared after several trials: the reflex could not be elicited after three continuous trials. The reflex could be elicited again if the intensity of stimulation was increased. The UG reflex also showed 'exhaustion': it could not be elicited, even with high intensities of stimulation, after 3 h of rest. All these findings were present when the UG reflex was elicited by applying pressure to the urethra or when it was evoked by the electrical stimulation to the pudendal nerve. According to these findings, it can be concluded that the UG reflex maintains some of the features that are found during ejaculation in intact animals. According to this view, it can be speculated that some of the mechanisms that control ejaculation in intact animals can be localized at a spinal level.