bluuebunny/crossref_metadata_2025_split huggingface dataset:
Pyeloureteral dynamics—Renal pelvis pressure‐flow relationship in pigs
Authors: Mortensen J. , Djurhuus J. C. 
Published: March 2007

AbstractIntrapelvic pressure in relation to Row was studied in the normal pyeloureter of the pig at progressing flow rates from 0 to 20 ml per minute. The mean pelvic pressure; before perfusion was started, was 6.1 cm H2O, increasing to 19.4 cm H2O at the highest perfusion rate. A significant increment in pressure occurred at a perfusion rate between 2 and 4 ml per minute. Thereafter, the mean pressure rise was linear with a correlation coefficient of 0.987 and an inclination of 0.27 cm H2O per ml.The study shows three phases of urine transport. At flow rates from 0 to 2 ml per minute, transport occurs at low pressure with a low resistance to flow through ureter. Between 2 ml and 4 ml per minute, a significant increase in intrapelvic pressure implicates an alteration of the peristaltic transport mechanism. It is presumed that the pressure increase is due to increased resistance in the ureter, probably caused by an impediment to passive filling. This impediment is probably due to the previous ureteral contraction, limiting the expansion of the fluid bolus. Above 4 ml per minute, transport takes place as a continuous flow through the ureter, which functions as a tube.
The motor nerve supply of the external urethral sphincter muscles: An electrophysiologic study
Authors: Vodusek D. B. , Light J. Keith 
Published: March 2007

AbstractThe term “intrinsic external urethral sphincter” has recently been applied to the striated muscle immediately surrounding the membranous urethra, thus distinguishing and separating it from the periurethral striated muscle which is a component of the pelvic floor. The innervation of the intrinsic external urethral sphincter is still controversial. Six male patients with a sustained spinal cord lesion above D‐4 underwent electrophysiological evaluation of the reflex and direct evoked responses to stimulation of the pudendal nerve branches in the perineal region. Recording of the motor unit potentials was performed using a catheter‐mounted concentric needle introduced into the intrinsic external urethral sphincter transurethrally. The results of this study indicate that the pudendal nerve, i.e., somatic, plays an important role in the innervation of the intrinsic external urethral muscle. It does not, however, exclude the possibility that the autonomic nervous system also innervates this muscle.
The after‐contraction in urodynamic micturition studies
Authors: Webster George D. , Koefoot R. Bruce , Zakrzewski Cary J. , Todd Shelby 
Published: March 2007

AbstractThe detrusor after‐contraction is an involuntary detrusor contraction occurring after the completion of voiding. These contractions were seen in the micturition studies of 20 patients undergoing videourodynamic study to investigate a variety of nonneurogenic urine voiding or storage problems. The contractions occurred in stable bladders on 15 of 20 occasions and only 2 of 20 cases exhibited obstructive urodynamics. Eleven of the 15 patients had hypersensitive bladders. We explore its possible etiology and conclude that it is of neither functional significance nor diagnostic value.
The failure of cystometry as a diagnostic aid in impotence
Authors: Fenemore Janet , Morales Alvaro , Condra Michael , Surridge David H. 
Published: March 2007

AbstractRecent evidence suggests an increasing recognition of the importance of organic factors in the etiology of impotence. This recognition has spurred the development of indices to reliably differentiate between psychogenic and organic types. This paper reports findings from the evaluation of the cystometric (CMG) assessment in impotence. Forty‐one impotent patients, in whom etiology (organic or psychogenic) had been clearly established using independent criteria, were investigated. The results show that abnormal CMG findings occurred approximately equally in both diagnostic groups, and that CMG values could not be used as a reliable indicator of etiology in impotence.
Animal models for penile erection studies
Authors: Lue Tom F. , Umraiya Matadeen , Takarnura Takao , Schmidt Richard A. , Tanagho Emil A. 
Published: March 2007

AbstractTo study the various aspects of penile erection, we created two animal models: (1) a monkey model, by implanting electrodes around the cavernous nerves, and (2) a dog model, by implanting electrodes around the cavernous and pudendal nerves. The cavernous nerves, which are branches of the pelvic plexus, travel along the posterolateral aspect of the prostate to innervate the erectile tisue of the penis. Electrostimulation of the cavernous nerves in 15 dogs and three monkeys induced prolonged erection. Because the anatomy of the penis in these animals is very close to that in man they offer an excellent model for the study of penile erection.
Functional response of the rabbit urinary bladder to anoxia and ischemia
Authors: Levin Robert M. , Brendler Katharine , Van Arsdalen Keith N. , Wein Alan J. 
Published: March 2007

AbstractThe effects of in‐vitro anoxia and in‐vivo ischemia on bladder function were studied using the in‐vitro whole‐bladder model. In addition to assessing the ability of the bladder to empty, this system provides a quantitative measurement of contractile activity. Anoxia was produced by equilibrating the isolated bladder with nitrogen instead of oxygen and ischemia was produced by clamping the arteries supplying the bladder for a period of one hour. The results of these studies can be summarized as follows: (1) The contractile response of the bladder to bethanechol did not decrease until the oxygen tension fell below 20% of normal; below this value the response decreased rapidly. (2) The ability of the bladder to contract declined gradually, as did the intracellular concentration of adenosine triphosphate. (3) The ability of the bladder to empty was lost immediately upon changing to an anoxic medium, as was the ability of bethanechol to produce a sustained contraction. (4) The bladder was able to fully recover from 60 minutes of in‐vitro anoxia, whereas 60 minutes of in‐vivo ischemia resulted in a permanent reduction in the contractile response to bethanechol.
Effect of extracellular calcium and calcium‐blocking agents on detrusor contractility: An in vitro study
Authors: Finkbeiner Alex E. 
Published: March 2007

AbstractThe effects of varying concentrations of calcium in the bathing solution and the effects of varying doses of the calcium‐blocking agents verapamil, diltiazem, and nifedipine on baseline tension, magnitude, and frequency of spontaneous contractions and on the contractile responses to acetylcholine, bethanechol, and electrical stimulation were tested on guinea pig bladder muscle strips suspended in a muscle bath.Over a wide range of calcium concentration (10−6 −4.8 × 10−3 M) no significant changes were noted in the aforementioned spontaneous and induced contractile activity. All parameters were, however, significantly depressed in a calcium‐free bathing solution.At doses of 1.0 and 2.0 μg/ml bath each of the calcium‐blocking agents significantly depressed the aforementioned spontaneous and induced smooth muscle contractile activity.
The role of reflexes in modifying the response to bethanechol chloride: A basis for selectivity of action on the bladder
Authors: Downie J. W. , Moochhala S. M. , Bialik G. J. 
Published: March 2007

AbstractWhen bethanechol is administered subcutaneously it induces a reflex‐dependent sustained bladder contraction, and causes significant salivation but has little effect on blood pressure or heart rate. This relative selectivity of action is important for the clinical utility of the drug. We tested the hypothesis that the absence of cardiovascular effects is due to reflex compensation by assessing bethanechol's actions after blocking these reflexes. In chloralose‐anesthetized cats the bladder was cannulated for pressure recording. Bethanechol (0.055–0.20 mg/kg SC) caused a sustained bladder contraction with no significant change in heart rate. During hexamethonium infusion (2 mg/min IV) SC bethanechol caused a fall in heart rate with no bladder contraction. Thus, strong cardiac compensatory reflexes normally prevent bethanechol‐induced bradycardia. The time course of bradycardia and bladder contraction in the same bethanechol injection were compared during blockade with the β1‐antagonist metoprolol (0.4 mg/kg IV). The nadir of the bradycardia did not coincide with the sustained bladder contraction. Furthermore, the time to peak bladder effect diminished with SC dose while the time to nadir of bradycardia did not. If the time course of the bradycardia reflects plasma bethanechol concentration, then triggering of the bladder reflex cannot be related directly to this level. The difference in latency may be related to distribution barriers or to response time differences.
The effect of aging on cholinergic receptor binding in the rat urinary bladder
Authors: Hayes Edward E. , McConnell Jo Ann , Benson George S. 
Published: March 2007

AbstractBinding sites with high affinity and specificity for [3H]quinuclidinyl benzilate (QNB), a cholinergic muscarinic receptor antagonist, were found in homogenates of rat urinary bladder. Atropine and scopolamine inhibited 50% of the specifically bound [3H]QNB (IC50) at a concentration of approximately 2 nM, whereas the agonist oxotremorine had an IC50 of 580 nM. By contrast, the IC50 for the ganglionic nicotinic antagonist mecamylamine was greater than 100,000 nM. These values are similar to those reported for [3H]QNB binding sites in rat brain.[3H]QNB binding was characterized in rat bladder obtained from animals aged 6, 16, and 26 months. No differences in either the number of binding sites or the affinity constant for the radioligand were noted between these groups, suggesting that there are no agerelated alterations in muscarinic receptor recognition sites in this organ.
Continuous overnight monitoring of bladder activity in vesicoureteral reflux patients: I. Method
Authors: Nielsen J. Bugge , Nøsrgaard J. P. , SøSrensen S. Schwartz , JøSrgensen T. Munch , Djurhuus J. C. 
Published: March 2007

AbstractA measurement system for monitoring bladder activity during sleep has been established. It includes bladder pressure measurements via suprapubic catheters, measurements of abdominal pressure activity via a rectally placed catheter, measurements of pelvic floor activity via surface electrodes placed perianally, and detections of involuntary voidings during sleep by a specially designed marking and alarm system. The system has been applied to 50 children with vesicoureteral reflux. In 40 patients, monitoring succeeded without discomfort to the patients. Preliminary analysis revealed bladder activity in all patients during sleep, an activity which is undergoing further analysis.
Effect of bilateral sacral decentralization on detrusor contractility and passive properties in dog
Authors: Ghoniern Gamal M. , Regnier Claude H. , Biancani Piero , Johnson Lewis , Susset Jacques G. 
Published: March 2007

AbstractA series of five dogs underwent complete parasympathetic decentralization through a lumbosacral laminectomy. A full‐thickness biopsy was taken from the anterior wall of the bladder before and 12 weeks after surgery. Both mucosa and adventitia were dissected out and muscle layer was cut into several consecutive longitudinal strips. Each strip was mounted in a muscle chamber and frequencyresponse curves were obtained at different pulse duration. Activelpassive force‐length relationships were then obtained under condi tions of maximal electrical stimulation (100 V, 2 msec, 40 cps), by stretching the strips in successive increments until length of maximal active force development was reached. Curves were normalized per unit cross‐sectional area of muscle. The maximum active stress of the specimens was taken as a measure of bladder contractility, and the rate of exponential increase in passive stress with strain (ratio of deformed to undeformed length) as a measure of detrusor stiffness.Twelve weeks after detrusor decentralization the following changes were found: (1) The frequency that yielded maximum contraction was 10 cps at 2‐ and 5‐;msec pulse duration as compared to 40 cps in controls at every pulse duration. (2) The maximum active stress was 123.9 ± 13.8 vs 244.7 ± 24.7 gm/cm2 in controls (p<.001). (3) The level of strain corresponding to the maximal active stress was significantly reduced. (4) The stiffness of the bladder wall was markedly increased; the rate of exponential increase was 4.47 ± 0.63 vs 2.19 ± 0.42 in controls (p<.001). (5) Thickness of the bladder wall was significantly increased (7 ± 1 vs 4 ± 1 mm; p<.001). (6) Histology sections of the specimens demonstrated collagen infiltration in all layers as well as smooth muscle hyperplasia.In summary, the effects of parasympathetic decentralization of the bladder wall are collagen infiltration, increased thickness, increased stiffness, and decreased contractility.
Urodynamic evaluation of the bilharzial urinary bladder
Authors: Abdel‐Hakim Amr , Shoukry Lsmail , Fam Aziz , Safwat Mohamed , Elhilali Mostafa M. 
Published: March 2007

AbstractUrodynamic evaluations of 63 male bilharzial patients and 25 normal males were included in the present work. According to the uroflowmetric parameters, patients were classified into two groups: those with normal voiding (38 patients) and those with impaired voiding (25 patients). Fluid cystometry followed by a micturition study were conducted in all patients with impaired voiding, 14 patients with normal micturition, and for two of the control group. The urodynamic data were computed and analyzed. Nineteen patients with bilharzial calcification of the urinary bladder underwent the same urodynamic evaluation. No urodynamic differences were found between the control group, the patients with normal voiding, and the patients with bilharzial bladder calcification. Patients with impaired voiding showed a significantly lower peak flow and longer micturition time; the voiding pressures and the abdominal contribution (%) were also significantly higher. Three factors were associated with impairment of micturition in our patients: (1) bladder outlet obstruction, (2) hypoactive detrusor, and () high‐grade vesicoureteral reflux.
Intrinsic neuromuscular defects in the neurogenic bladder. 1. Short‐term ultrastructural changes in muscular innervation of the decentralized feline bladder base following unilateral sacral ventral rhizotomy
Authors: Elbadawi Ahmad , Atta Mohamed A. , Franck Joel L. 
Published: March 2007

AbstractThe morphology of cholinergic and adrenergic muscular nerves of the feline bladder base was studied ultrastructurally 2, 3, and 4 weeks following its decentralization by unilateral sacral ventral rhizotomy. In all samples, there was widespread transsynaptic degeneration of cholinergic axon terminals and varicosities, with loss of neuroeffector junctions. This was associated with preservation of most adrenergic axons, and — especially in the 4‐week samples—with concurrent early regeneration or sprouting in many cholinergic and adrenergic axons. The findings are discussed in relation to neural ultrastructure in other known models of axonal degeneration, and to the pathogenesis of neurogenic dysfunction of the parasympathetic‐decentralized bladder. The concurrent degenerative and early regenerative axonal changes herein observed in such a bladder (1) suggest that the degeneration of cholinergic axons occurring shortly after rhizotomy is reversible, and probably is compensated for by developing adrenergic hyperinnervation; (2) support the existence of mutual peripheral cholinergic/adrenergic neurotrophism in the vesical muscularis; and (3) provide a probable structural basis for the altered motor and autonomic drug responses of the parasympathetic‐decentralized bladder.
Comparative effects of five tricyclic compounds on the rabbit urinary bladder
Authors: Levin Robert M. , Wein Alan J. 
Published: March 2007

AbstractThe tricyclic antidepressant irniprarnine is widely utilized in treating a number of the disorders of micturition. Its effect on urinary tract smooth muscle is believed to occur through several mechanisms including direct antimuscarinic activity, direct smooth muscle relaxation, and indirectly by the inhibition of noradrenaline uptake into adrenergic neurons. The present study compared the potency of five tricyclic compounds on the contractile response of the rabbit urinary bladder to bethanechol. In addition, the direct antimuscarinic potency of these agents on radioligand binding to muscarinic receptors isolated from rabbit urinary bladder was determined.Of the five agents tested (imipramine, desrnethylirnipramine, amitriptyline, nortripty‐line, and doxapine), doxapine was found to be significantly more potent than the other agents with respect to both antimuscarinic and musculotropic relaxant activity.
Effect of lsoproterenol and EGTA on the volume‐pressure relationship of the in vitro whole bladder preparation
Authors: Levin Robert M. , Goldman Michele , Wein Alan J. 
Published: March 2007

AbstractIn a previous study comparing the pharmacological response of smooth muscle strips isolated from rabbit urinary bladder with the response of the whole bladder preparation, we observed that although isoproterenol stimulated a marked decrease in isometric tension in the muscle strips, isoproterenol only slightly decreased intravesical pressure (whole bladder preparation).We have recently modified our whole bladder system so that we can now quantitatively
determine the effect of drugs on bladder volume at constant pressure as well as on
intravesical pressure at constant volume. Using this system we have reinvestigated the
effect of isoproterenol and have demonstrated that although isoproterenol has only a slight
effect on intravesical pressure, this minor effect on pressure resulted in a marked increase
in whole bladder volume, and a corresponding increase in cystometric compliance.
Effect of metoclopramide on ejaculatory threshold in a group of premature ejaculators
Authors: Wabrek Alan J. 
Published: March 2007

AbstractThe exact etiology of premature ejaculation is not known. Recent data using rats has demonstrated that dopamine agonists can lower ejaculatory thresholds while pretreatment with substituted benzamides will block that effect. Metoclopramide, the only drug in the group available in the United States, and a placebo were given to 12 premature ejaculators in a double‐blind crossover fashion. Couples had intercourse on Wednesdays and Saturdays for four weeks. Ejaculatory latencies were recorded separately by husbands and wives on a 1–5 scale. There was no statistical difference in perception of ejaculatory latency between metoclopramide‐ and placebo‐treated coiti although the P values for the wives' perception was.067. An added observation was that approximately 80% of premature ejaculators had palmar hyperhidrosis. It is conjectured that early ejaculation and palmar hidrosis are manifestations of sympathetically mediated “overreactivity”.
The effectiveness of bethanechol chloride in lower motor neuron lesions: The importance of mode of administration
Authors: Awad Said A. , McGinnis Rosemary H. , Downie John W. 
Published: March 2007

AbstractThe therapeutic effectiveness of bethanechol has been the subject of controversy. This study documents its effectiveness in initiating micturition and lowering postvoid residual urine when given subcutaneously to seven patients with lower motor neuron lesions. By contrast, the effect was not as consistent when bethanecol was given orally. Disturbing side effects seem to occur with repeated subcutaneous administration. The development of methods by which serum levels could be accurately measured is recommended.
Possible errors in uroflowmetry
Authors: Lief Matthew , Khan Zafar , Leiter Elliot , Melman Arnold 
Published: March 2007

AbstractThe possibility of alteration of uroflow rates by rapid bladder filling was evaluted in 61 consecutive patients referred for urodynamic evaluation. Nine of the 28 patients who were able to void did in fact demonstrate a significant reduction in uroflow rates after the bladder had been rapidly filled. Thus, the manner of obtaining the uroflow should be taken into account when making a clinical decision based on that test.
Anti‐incontinence surgery in females with detrusor instability
Authors: Lockhart Jorge L. , Vorstman Bert , Politano Victor A. 
Published: March 2007

AbstractFifty‐eight females with clinical stress or stress and urge incontinence were evaluated urodynamically and treated surgically. Forty‐six females (group A) presented with a stable detrusor or low‐pressure instability (below 25 cm of water), and 12 (group B) had high‐pressure instability (above 25 cm of water). Overall surgical results were worse in group B. Analyzing the urodynamic and surgical results, detrusor pressure recording may have surgical predictive value.
Bethanechol chloride in urology—A discussion of issues
Authors: Downie John W. 
Published: March 2007

AbstractThe widespread and long‐standing use of bethanechol chloride in urology attests as much to the lack of a suitable alternative as it does to the drug's perceived efficacy. The bases for both positive and negative conclusions about bethanechol's usefulness are critically examined and areas of controversy and uncertainty highlighted. An attempt is made to rationalize bethanechol's effects in the light of recent investigations into its mechanism of action but clearly more information is required for a full understanding of the drug's action and its' appropriate place in urologic practice.
Urethral sensitivity to α‐adrenoceptor stimulation and blockade in patients with parasympathetically decentralized lower urinary tract and in healthy volunteers
Authors: Mattiasson Anders , Andersson Karl‐Erik , Sjöugren Christer 
Published: March 2007

AbstractThe urethral pressure responses to i.v. infusion of increasing doses of noradrenaline (NA) and to i.v. injection of a single dose of phentolamine were compared in male and female patients with parasympathetically decentralized lower urinary tract and in normal volunteers of both sexes. Maximum urethral pressure (MUP) was significantly lower in the patients than in the volunteers. NA caused a dose‐dependent increase in MUP in all subjects; the absolute increase was greater in the patients. However, even at the highest rates of NA infusion, the MUP of the patients did not reach the resting pressure of the normal volunteers', and the dose‐response relations for the NA effect did not differ between patients and normal subjects. Phentolamine reduced the urethral pressure significantly less in male volunteers than in the other subjects. It is concluded that patients with parasympathetically decentralized lower urinary tract have no urethral smooth muscle supersensitivity to NA, and that it cannot be excluded that the pelvic, parasympathetic innervation contributes to the regulation of pressure in both the male and female urethra.