bluuebunny/crossref_metadata_2025_split huggingface dataset:
The effect of hexamethonium on the distension‐induced contractile activity of the rat bladder: Evidence for the existence of a spinal ‘short‐loop’ vesicovestioal reflex in rats
Authors: Maggi Carlo Alberto , Santicioli Paolo , Meli Alberto 
Published: March 2007

AbstractSaline distension of the bladder in urethane‐anaesthetized rats elicited three types of phasic contractions: (a) a low amplitude (<4 mmHg) asynchronous contractile activity which is hexamethonium‐resistant; (b) an intermediate amplitude (8–16 mmHg) rhythmic contractile activity that was still present in spinal (C2‐C3) rats and was eliminated by hexamethonium; and (c) a high amplitude (>20 mmHg) rhythmic contractile activity that was eliminated by spinal cord transection or hexamethonium. All types of hexamethonium‐sensitive rhythmic contractile activity having an amplitude higher than 4–6 mmHg were prevented by destruction of the lumbosacral spinal cord. It is concluded that in adult rats two distinct types of vesicovesical reflex activity organized at spinal and supraspinal level, respectively, could be elicited by distension at a physiological‐like filling rate.
Subtrigonal phenol injection: Lack of effect in the treatment of detrusor hyperactivity
Authors: Nordling J. , Steven K. , Meyhoff H. H. , Hald Tage 
Published: March 2007

AbstractSubtrigonal phenol injections were administered to 16 patients with detrusor hyperreflexia resistant to conventional treatment. Two patients experienced a temporary improvement lasting 2 months; in eight patients there was no effect; four developed urinary retention, which was treated by intermittent catheterization in three and by an indwelling catheter in one; symptoms deteriorated in one, and one patient developed a vesico‐vaginal fistula requiring urinary diversion after a second injection treatment. Subtrigonal phenol injection appears to be an ineffective treatment of severe detrusor hyperreflexia in this group of patients.
Continuous urethral pressure measurement in women with unstable detrusor
Authors: Sørensen S. , Nørgaard J. P. , Djurhuus J. C. 
Published: March 2007

AbstractTo study the role of the urethra in bladder instability, we performed continuous urethrocystometry in 16 patients with verified unstable detrusor and found two qualitatively different pressure oscillations in the urethra: (1) continuous rhythmic pressure waves, characterized by frequency and pressure amplitude and (2) sudden and consistent urethral pressure drops of 35 cm H2O occurring on average at mean time intervals of 3.5 seconds prior to the onset of the detrusor contraction. Simultaneous pelvic floor electromyographic (EMG) registration showed that the urethral pressure drop occurred either during decreased, unchanged, or increased pelvic floor activity. Restoration of the urethral pressure to its previous level was also unrelated to the pelvic floor EMG activity. Increased EMG activity at the onset of urethral pressure drops was not sufficient to suppress the urethral pressure drop, but could abolish the detrusor contraction.These findings suggest that the unstable detrusor is of a complex pathophysiological origin and involves both storage and micturition as well as detrusor and urethral function.
Urethral instability: Diagnosis based on variations of the maximum urethral pressure in normal climacteric women
Authors: Versi Eboo , Cardozo Linda 
Published: March 2007

AbstractThe existence of urethral instability as a pathological entity is debated, and this discussion is hampered by the lack of rational guidelines for its diagnosis. The literature is not uniform, as different authors have chosen arbitrary values of urethral pressure fluctuations for characterizing the condition. To attempt to clarify the situation, 85 healthy climacteric women have been examined. They had normal flow rates and were found to be normal on videocystourethrography. Their urethral pressure profile traces (microtransducer technique) were examined for fluctuations in the maximum urethral pressure (MUP). Given that the MUP decreases with age and that in this data set fluctuation in the MUP (Δ MUP) is dependent upon the MUP, the ratio of Δ MUP divided by MUP has been examined. Statistical analysis of the derived distribution suggests that fluctuations of MUP that are greater than one‐third of the resting MUP fall outside the 99% confidence limit and so should be regarded as abnormal. If, when this occurs, the patient is regarded as having urethral instability, then the incidence of urethral instability in our normal climacteric women is 14 ± 4%. We suggest that this method of analysis should be employed to arrive at a rational statistical threshold for the diagnosis of urethral instability. Only then will it be possible to explore the clinical implications of this condition.
Significance of electromyographic changes in the external urinary sphincter
Authors: Davis L. , Khan Z. 
Published: March 2007

AbstractThe diagnostic role of electromyography of external urinary sphincter is well established in neurologically compromised patients. A brief historical review and methodology is described. For those who are not familiar with this modality, the character and clinical significance of abnormal potentials has been described. The coordination of bladder and sphincter mechanism and its abnormality is explained. Our experience with various neurological disorders is listed. It includes myelodysplasia, transverse myelitis, multiple sclerosis, herpes zoster, Parkinson disease, and some cerebral disorders. Any apparent statistical difference is due to the highly selected nature of the cases.
Do “Conscious” and “Reflex” micturition have a separate sensory input? Implications for clinical urodynamics
Authors: Maggi Carlo Alberto , Meli Alberto 
Published: March 2007

AbstractAnatomical, neurophysiological, pharmacological, and clinical observations indicate the existence of multiple sensory pathways relaying information from the lower urinary tract to the central nervous system. The sensory input that activates “voluntary” (in humans) or “conscious” (in animals) micturition may be, at least in part, separate from that which activates “reflex” micturition. Recent observations obtained with capsaicin, a sensory neuron blocking agent, indicate that multiple sensory pathways may activate micturition and that these systems operate at a different threshold, eg, certain sensory systems are particularly sensitive to variations in filling rate. These advances in the physiopharmacology of the afferent branch of micturition suggest that the use of very different filling rates from one laboratory to another may be a major cause of heterogenicity of results in clinical urodynamics. Moreover, a complete and meaningful evaluation of the sensory function regulating micturition should include evaluation of the bladder response to both “low” (physiological) and “high” (provocative) filling rates.
Biochemical characterization of the rabbit urinary bladder base and body
Authors: Levin Robert M. , Haugaard Niels , Ruggieri Michael R. , Wein Alan J. 
Published: March 2007

AbstractFunctionally, the urinary bladder can be divided into two sections: the bladder body and bladder base. Pharmacologically, the bladder body responds to a greater extent than the bladder base to cholinergic agonists (contraction), beta‐adrenergic agonists (relaxation), and purinergic agonists (contraction), whereas the bladder base responds to a greater extent than the bladder body to alpha‐adrenergic agonists (contraction). The autonomic receptor density parallels the pharmacological response; that is, the bladder body contains higher densities of muscarinic cholinergic and beta‐adrenergic receptors than the bladder base, whereas the base contains a higher density of alpha‐adrenergic receptors. The purpose of this present study was to compare a variety of biochemical factors between the rabbit urinary bladder base and body.Sections of rabbit bladder body and base were rapidly dissected and frozen in liquid nitrogen. Tissue concentrations of DNA, RNA, hydroxyproline, lipids, glycogen, cyclic AMP, CP, ATP, ADP, and AMP were determined. The results demonstrated that the bladder base contained a 34% greater concentration of DNA, whereas the bladder body contained a 127% greater concentration of RNA. The bladder base contained 39.6% and 36% greater concentrations of hydroxyproline and glycogen, respectively. The concentration of lipids, cyclic AMP, and adenine nucleotides was equal in the two areas. The observed differences between bladder body and base may be related to the significantly greater work (energy utilized to actively expel urine) performed by the bladder body.
Urethral pressure variations in women with neurourological symptoms: I. Relationship to urethral and pelvic floor striated muscle
Authors: Kulseng‐Hanssen S. , Stien R. , Fønstelien E. 
Published: March 2007

AbstractSimultaneous urethrocystometry and electromyography (EMG) of the urethral and pelvic floor striated muscle were performed in 42 gynecological patients with neurourological symptoms. Their maximum urethral pressure varied between 20 and 124 cm H2O. A correlation analysis was performed between the maximum urethral pressure and the integrated EMG of the urethral striated muscle and the pelvic floor striated muscle. The analyses were performed on results obtained in 1‐min periods during bladder filling before first desire to void was reported, when first desire to void was reported, and when a strong desire to void was reported.In 21 patients no correlation was found between the urethral and pelvic floor striated muscle activity and the maximum urethral pressure at any stage of bladder filling. In the other 21 patients a correlation was found in at least 1 of the 3 stages. At all stages of bladder filling a correlation was found significantly more often between the maximum urethral pressure and the striated urethral muscle EMG than between the maximum urethral pressure and the striated pelvic floor muscle EMG. Thus, activity of the urethral striated muscle cannot be reliably studied in an EMG recording from the pelvic floor striated muscle. In the same patient, periods with a correlation could be succeeded by periods without a correlation. Thus, the urethral pressure variations may in the same patient sometimes be caused mainly by the urethral striated muscle and sometimes mainly by the urethral smooth muscle.
Coexistence of prostate cancer and dysfunctional bladder neck obstruction
Authors: McCulloch Allen W. , Woodside Jeffrey R. , Lackner L. Henry , Key Charles R. 
Published: March 2007

AbstractThe etiology of dysfunctional bladder neck obstruction remains elusive. Obstruction has been attributed to muscular hypertrophy, fibrosis, scarring, and neurologic dysfunction of the bladder neck opening mechanism. We describe two patients with urodynamic findings of dysfunctional bladder neck obstruction who proved to have stage A1 prostate adenocarcinoma on transurethral prostate biopsies obtained at the time of surgery. We recommend that the transurethral surgical treatment of men over the age of 40 years with dysfunctional bladder neck obstruction include a biopsy for histological examination.
Effects of atropine on bladder capacity and instability in rats with bladder hypertrophy
Authors: Malmgren A. , Sjögren C. , Andersson K.‐E. , Andersson P. O. 
Published: March 2007

AbstractCystometries were performed in conscious normal rats and in rats with infravesical outflow obstruction in the absence and presence of atropine. The effects were evaluated with regard to bladder capacity, bladder compliance, threshold pressure, micturition volume, residual volume, micturition pressure, and spontaneous contractile activity. In control rats following the administration of atropine, bladder capacity increased in six of seven experiments, but this effect was not statistically significant. No other cystometrical variable was changed in control rats by muscarinic receptor blockade. Bladder capacity in obstructed rats was clearly larger than in control rats (mean 4.4 ± 1.1 and 0.20 ± 0.02 ml, respectively). In obstructed rats atropine significantly increased bladder capacity from 4.4 ± 1.1 to 7.9 ± 1.2 ml. Further, the obstructed rats were characterized by an increase in threshold pressure and residual volume, and a decrease in micturition volume after atropine administration. Micturition pressure in obstructed rats was higher than in control rats (131 ± 29 and 33 ± 6 cm H2O, respectively). In obstructed rats, administration of atropine decreased micturition pressure, indicating a cholinergic component participating in bladder contraction. A clear‐cut bladder instability was observed in all obstructed rats, and part of the contractions remained after atropine, suggesting a myogenic or a noncholinergic nervous origin.
Studies on the biphasic nature of urinary bladder contraction and function
Authors: Levin Robert M. , Ruggieri Michael R. , Gill Harcharan S. , Haugaard Niels , Wein Alan J. 
Published: March 2007

AbstractThe function of the urinary bladder is to store and expell urine. Micturition is accomplished via a coordinated, well‐sustained contraction of sufficient force to expel the entire contents of the urinary bladder. Studies in several labs have demonstrated that a functional bladder contraction consists of two phases: the first phase is represented by a rapid rise in intravesical pressure (isometric contraction) to a peak, followed by a prolonged period of increased (sustained) intravesical pressure (tension). Using isolated strip techniques, the in vitro whole bladder model, and several metabolic methodologies, we have studied contractile, functional, and biochemical parameters of these two phases of contraction.The results of our studies were as follows: 1) There was a small but significant decrease in net ATP at the peak of contraction, but not during the plateau phase. Creatine phosphate (CP) was significantly reduced at both times. 2) There was a rapid decrease in NADH fluorescence during the peak phase of contraction, which indicates an increase in oxidative metabolisvm. 3) The ED50 for the fluorescence response to bethanechol was significantly lower than the ED50 for contraction. 4) Whereas anoxia produced a gradual decline in both intracellular ATP and peak contraction, there was an immediate loss in the ability to maintain a contraction (ability of the bladder to empty).The results of these studies indicate that whereas preformed ATP mediates the initial contractile response to bethanechol, the plateau phase of bladder contraction (and the ability of the bladder to empty) may be mediated by high‐energy intermediates of oxidative phosphorylation (aerobic metabolism).
Comparative response of smooth muscle strips of bladder and bowel to various pharmacological agents
Authors: Batra Ashok K. , Wein Alan J. , Ruggieri Michael R. , Levin Robert M. 
Published: March 2007

AbstractIntestinal segments are commonly incorporated in the urinary system as conduits, reservoirs, and as implants in augmentations of bladders. This practice, initiated in 1888 by Tizzone, only became popular in the 1950s. Although both bladder and intestine are composed primarily of smooth muscle, there are significant morphological and functional differences between these tissues. This present study compares the pharmacological properties of intestinal smooth muscle to those of bladder smooth muscle. Ileum was taken as a representative section from small intestine, sigmoid colon from the large bowel, and the bladder body from the urinary bladder.The results can be summarized as follows: Bethanechol (cholinergic agonist) produced a rapid and sustained increase in tension in the bladder, a marked increase in the amplitude and frequency of phasic contractions in the ileum, and a sustained increase in tension in the sigmoid colon. Methoxamine (α‐adrenergic agonist) and ATP (purinergic agonist) produced an increase in tension in the bladder, and reduced the tension in both ileum and sigmoid. Isoproterenol (β‐adrenergic agonist) produced a relaxation in all three tissues.
Inhibitory muscarinic receptors and α‐adrenoceptors on cholinergic axon terminals in the urethra of rabbit and man
Authors: Mattiasson Anders , Andersson Karl‐Erik , Sjögren Christer 
Published: March 2007

AbstractIsolated smooth‐muscle preparations from the rabbit and human urethra were incubated with 3H‐choline, and the influence of drugs on the electrically induced release of 3H was studied. In both rabbit and human urethral smooth muscle, the release was well reproducible and abolished in the presence of tetrodotoxin, indicating a nervous origin. By means of drugs stimulating (carbachol, nicotine amide) and blocking (scopolamine, hexamethonium) cholinoceptors, release‐inhibiting muscarinic but not nicotinic receptors could be demonstrated on the cholinergic axon terminals. The stimulation‐induced efflux of 3H was significantly and concentration‐dependently inhibited by noradrenaline (NA) and the selective α2‐adrenoceptor agonist, clonidine. The effects of NA and clonidine were abolished by phentolamine. Phentolamine by itself did not influence the release, nor did rauwolscine. Morphological investigations have revealed close contacts between adrenergic and cholinergic axon terminals, and the occurrence of muscarinic receptors on adrenergic axon terminals inhibiting release of NA in the urethra has previously been demonstrated. The present results therefore suggest the possibility of a mutual interaction between adrenergic and cholinergic neurons at the axon‐terminal level in the urethra.
New method for static and dynamic measurement of related values of cross‐sectional area and pressure in the female urethra
Authors: Lose Gunnar , Colstrup Hans , Saksager Kim , Kristensen Jørgen K. 
Published: March 2007

AbstractA new probe for simultaneous measurement of cross‐sectional area and pressure in the female urethra has been devised based on the field‐gradient principle and microtip transducer technique. The system permits measurement during fast inductions of well‐defined cross‐sectional areas in segments of the urethra (experimental stress episodes), contraction of the pelvic floor, and coughing. The measurements make possible a description of the static and dynamic mechanical properties of the female urethra in terms of compliance or elastance, uninstrumented closure pressure, and hysteresis. Furthermore, urethral closure function can be evaluated in terms of work or power created by the urethral closure apparatus during contraction of the pelvic floor and during coughing.
Electrophysiological correlates of sensory innervation of the vesico‐urethral junction and urethra in man
Authors: Sarica Yakup , Karacan Ismet 
Published: March 2007

AbstractTo investigate urethral sensory innervation in man, cerebral evoked potentials (CEPs) and bulbocavernous reflex (BCR) were recorded by stimulation of vesico‐urethral junction (VUJ), prostatic and distal urethra, and penile skin. A specially produced catheter with a pair of electrodes was used for bipolar stimulation along the lower urinary tract. In comparison to the potentials evoked by distal urethral stimulation, the shape differences and protracted latency of CEPs to VUJ stimulation suggest that the distal and proximal urethra are innervated by different peripheral afferents. Similarities of CEPs and BCR latencies produced by prostatic urethral and VUJ stimulation indicate that the sensory innervation of the prostatic urethra is provided by pelvic nerve afferents. The remaining distal parts of the urethra are innervated by pudendal nerves. This is indicated by shape similarities and latency characteristics of both CEPs and BCR when the distal urethra and glans skin are stimulated.
Functional effect of chronic ischemia on the rabbit urinary bladder
Authors: Lin Alex Tong‐Long , Wein Alan J. , Gill Harcharan S. , Levin Robert M. 
Published: March 2007

AbstractThe functional effect of partial ischemia of the rabbit urinary bladder was studied. Unilateral ischemia was created by ligation of one of the two vesical arteries that supply the rabbit bladder. The effect of 1‐day, 1‐, 2‐, and 4‐week chronic unilateral ischemia on in vivo and in vitro cystometry, and the functional response of the in vitro whole bladder model to field stimulation and bethanechol were determined. Within 1 day following the creation of unilateral ischemia, the bladder became hyperreflexic with decreased compliance. This condition was observed in the 1‐ and 2‐week groups. By 4 weeks, the hyperreflexia had decreased, and the compliance increased significantly. Peak pressure generation for in vitro whole bladder in response to field and bethanechol (500 μm) stimulation was maintained the same as control for all groups. However, the ability of the bladder to empty was diminished to about 50% of control values in the 1‐day, 1‐week, and 2‐week groups. The ability to empty recovered to a significant degree by 4 weeks for both field stimulation and bethanechol. Our results show that the bladder function cannot be judged by pressure generation alone; a study of compliance and the ability to empty should be performed to give a true indication of the functional state of the bladder.
Urodynamic responses to sacral stimulation in the chronic spinal dog
Authors: Walter J. S. , Wheeler J. S. , Robinson C. J. , Bolam J. , Wurster R. D. 
Published: March 2007

AbstractRecent reports have shown that electrical stimulation of the bladder wall or sacral nerves can be effective for bladder management in the spinal‐cord‐injured (SCI) patient. However, unacceptable bladder pressures and urethral resistances have been reported in many of these patients following such stimulation procedures. These problems were evaluated in this study using epidural electrodes in the sacral canal of the chronic spinal male dog. We found that bladder reflex activity is important for sacral stimulation to induce effective voiding. Voiding in response to stimulation was poor during the first week following spinal injury but improved during the next 2 weeks. A significant increase in bladder pressure in response to stimulation occurred during this period, but urethral resistance remained unchanged. Urethral resistance, the ratio of bladder pressure to voiding rate, was lower for poststimulus voiding than for voiding during continuous stimulation. Bladder compliance, measured via cystometry, was improved in one spinal dog during a period of sacral stimulation. However, an adverse trend toward increased bladder thickness was seen on postmortem examination. Overall, this minimally invasive method was encouraging and may be efficacious for bladder control in some SCI patients.