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PubMed1996

Spinal dorsal horn neurons responding to noxious distension of the ureter in anesthetized rats.

1. Stimulation of the ureter in humans evokes only painful sensations. A large proportion of ureteric afferents show high activation thresholds to ureter pressure increases and encode stimuli within the noxious range. However, little is known about how these properties are reflected in the central processing of ureteric information. In this study, dorsal horn neurons recorded in the left side of the T12-L1 spinal cord of anesthetized rats have been tested for responses to innocuous and noxious pressure stimuli applied to the ipsilateral ureter. 2. Single-unit recordings were made from 76 neurons with somatic receptive fields on the left flank, of which 57 were fully characterized and tested by raising the ureter pressure to 80 mmHg for 30 s. Of these 57 neurons, 24 (42%) were influenced by the ureter stimulus, as follows: 18 were excited, 2 were inhibited, and 4 showed changes in background activity and/or in somatic receptive field area, without a time-locked change in firing rate. The remaining 33 cells (58%) showed no changes in firing rate, background activity, somatic receptive field area, or input properties as a result of ureter stimulation. 3. Neurons responding to the 80-mmHg stimulus were further tested with a range of ureter pressures (5-100 mmHg). No responses were evoked by stimuli of < 20 mmHg, and responses observed were proportional to stimulus intensity. Excitatory responses showed a long onset latency (median = 23 s) and long afterdischarges (median = 145 s). 4. All neurons with ureter input had nociceptive somatic inputs. When compared with neurons without ureter input, cells with ureter input were more likely to show background activity (80 vs. 27%) and more likely to have bilateral somatic receptive fields (30 vs. 6%). Neurons with ureter input had higher rates of background activity and larger somatic receptive fields. Ureter stimulation also produced changes in the somatic receptive field area of neurons excited or inhibited by the stimulus, indicating a high degree of plasticity in the ureteric nociceptive pathway. 5. We conclude that the characteristics of the responses of dorsal horn neurons with ureter input to noxious and innocuous ureter stimulation indicate that they receive ureteric input mainly from high-threshold afferents, and that their response properties correlate well with ureteric pain sensation in humans.

Animals↗

PubMed1992

[Adrenergic regulation of the contractility of the human and canine ureters].

Investigations on the isolated pieces from upper part of human ureters and upper and lower parts of dog ureters were performed. Isometric contractions during electrical stimulation in Lock solution (37 degrees C) and their changes after adrenomimetic drug and adrenoblocking drug perfusion were studied. The pieces of human ureters had more average weight and rest tension, but less isometric tension during rhythmic electrical stimulation and more pronounced hypersodium contracture in contrast to dog ureters. Adrenaline and noradrenaline augmented contractions of human and dog ureters. Isadrin increased the contractility of the upper parts of human ureters and the lower parts of dog ureters, but decreased--the upper segments of dog ureters. Adrenoblocking agents modified the action of adrenomimetics. After blockade of alpha-receptors by phentolamine, isadrin decreased the contractions of all studied pieces of ureters, however, adrenaline decreased contractility of human ureters but increased--dog ureters. It may be proposed, that there are alpha 1 and alpha 2 receptors, that stimulated the contractility of human and dog ureters, beta 1 adrenoreceptors, that inhibited the contractions during blockade of alpha-receptors, and beta 2-receptors, that in these conditions increased the contractions of dog ureter but decreased the contractions of human ureters.

Animals↗

PubMed1996

Electroureterogram in the obstructed ureter and vesicoureteral reflux.

BACKGROUND: An electroureterogram (EUG) was identified for the normal ureter (A. Shafik, 1996). It was postulated that the EUG might change under pathologic ureteric conditions. This communication studies the EUG pattern in the obstructed ureter and in the ureter with vesicoureteral reflux. MATERIAL AND METHODS: 11 patients with stricture of the lower end of ureter (all men; mean age 36.6 +/- 6.2 years) were studied. Urography showed a hugely dilated ureter. Nineteen patients with vesicoureteral reflux (13 women and 6 men; mean age 32.8 +/- 5.6 years) had moderately dilated ureters. All patients were scheduled for operative correction in the course of which the current study was done. A monopolar silver-silver chloride electrode was applied to each of the upper, middle, and lower third of the ureter. The EUG activity and intraureteric pressure were recorded before and immediately after ureteric reconstruction. RESULTS: The obstructed ureter showed a "silent" EUG. The refluxing ureter revealed three EUG patterns: silent, bradyureter (diminished frequency and amplitude of slow waves or pacesetter potentials, PPs), and ureteroarrhythmia (irregular PP frequency and amplitude). These patterns were reproducible when the tests were performed before or immediately after ureteric reconstruction. The intraureteric pressure in the strictured ureters was high and dropped after ureteric stricture resection. It recorded normal values in the refluxing ureter. CONCLUSIONS: It appears that ureteric dilatation interferes with the electric ureteric activity. The most dilated ureters showed a silent EUG while the least dilated exhibited bradyureter. The results have shown that the dilated ureter may display an abnormal EUG and that with the development of a noninvasive technique in the future, the EUG may be of diagnostic significance in ureteric disorders.

Adult↗

PubMed1995

Experimental study of ureteral free grafts. I. Surgical findings in transplanted and abandoned ureter.

OBJECTIVE: To develop two experimental models in rats to study the ureter under conditions of total devascularization and denervation. METHODS: The ureter was autotransplanted as an integrated autologous free graft (IAFG) or abandoned in the retroperitoneum as a non integrated autologous free graft (NIAFG). Both models were compared with a normal group and a surgical control group. Sixty-two rats were randomly distributed: Normal ureter (NU) group (n = 20); surgical control, only ureterolysis (SC) group (n = 15); abandoned ureter as NIAFG (AU) group (n = 13); reimplanted ureter as IAFG (RU) group (n = 14). RESULTS: SC group: in all cases a ureter with no alterations was observed although with slight periureteral fibrosis. AU group: some ureter specimens had a smaller caliber. Periureteral fibrosis was observed in all the cases. Vessel distribution was similar to that of the NU group. All the ureters conserved their lumen. 53.8% of the ureters showed spontaneous contractions and 100% contractions after mechanical stimulation. Cyst formation, necrosis, fistulas or stenosis of the lumen were not observed. RU group: microscopic findings of the ureter segment used as IAFG were compatible with those of a normal ureter. In all the cases a moderate degree of periureteral fibrosis was observed. In the majority of the cases a vascular framework of the fat immediately adjacent to the ureter was observed. In 13 of the 14 operated cases spontaneous contractions were observed. The ureteral segment used as IAFG showed no alterations in 10 cases and with alterations of various types in 4 cases. In 8 cases there was a greater or lesser degree of stenosis of the proximal suture. CONCLUSIONS: The surgical findings and the macroscopic aspects of the four groups show the viability of the ureter free graft, IAFG as well as the NIAFG, in spite of the macroscopic changes.

Animals↗

PubMed2001

Covering of the terminal ureter with de-serosalized muscle layer of the ileum for antireflux ureteroileostomy: an experimental study in dogs and a preliminary clinical trial.

We demonstrated a new operative technique for antireflux ureteroileostomy in dogs. The severed ureter was reimplanted into the isolated ileum. Ten terminal ureters were covered with a 2 x 2 cm2 section of de-serosalized ileal wall after direct ureteroileostomy, and another six terminal ureters were covered with a 2 x 2 cm2 section of non-de-serosalized full-thickness ileal wall. Thirteen ureters were directly anastomosed to the ileum without any additional procedures. The bladder was augmented by the detubularized ileum with the ureter. Postoperative evaluations on ureteral stenosis and reflux were performed monthly for 3 months. The ureters covered with the de-serosalized ileal wall prevented ureteral reflux even when the intravesical pressure climbed as high as 100 cm H2O. Although two of these ten ureters demonstrated strictures at the precise site of direct ureteroileostomy, the sections of the ureters covered with the de-serosalized ileal wall were opened and did not collapse. In the resected specimens, the terminal ureters were found in the intramural part of the ileum. The ureters covered with the full-thickness of ileal wall did not prevent reflux. Our method of covering the terminal ureter with the de-serosalized ileal wall worked well as an antireflux mechanism, and the intramural ureter did not cause ureteral stricture. After this animal experiment, we introduced this antireflux mechanism clinically.

Aged↗

PubMed2007

A radiological study on the anatomical proximity of the ureters and the cervix.

In order to evaluate risk factors for anatomical proximity between the cervix and the ureters the distance between the ureters and the cervix was measured in 499 computerized tomography (CT) studies at the most dorsal reflection of the ureters. The relationship between the ureter-cervical distance and the presence of pelvic pathology was assessed by correlation tests and regression analysis. Of the 499 CT studies, 252 demonstrated radiographic pathologies. Among abnormal scans, 126 (50%) involved cervical pathology. At least one ureter was within 0.5 cm of the cervix in 3.6% of patients with normal CT scans and in 10.3% of patients with cervical pathology. Overall, the right ureter was significantly closer to the cervix than the left (2.0 +/- -0.8 cm vs. 2.2 +/- 1.0 cm, p < 0.05). In cases were the pathology was limited to the cervix, the right ureter was more distant than the left (2.0 +/- 0.6 cm vs. 1.7 +/- 0.6 cm, p < 0.05). The distance between the ureters and the cervix was inversely correlated with the lateral diameter of the cervix (r = 0.18, p < 0.001) and its anterior-posterior diameter (r = 0.11, p < 0.001). Age did not correlate with the distance of the ureters from the cervix (r = 0.002, p = N.S). In conclusion, approximately 10% of patients with cervical pathology can be expected to have a ureter proximate less than 5 mm from the cervix. For patients with cervical pathology undergoing a planned hysterectomy, preoperative measurement of cervical-ureteric distance may be warranted. In these circumstances intra-operative measures to protect the ureter and ascertain its integrity may be invaluable.

Adult↗

PubMed1998

Contractile properties of ureters from rats with infravesical urinary outlet obstruction.

Mechanical properties of ureters from rats with infravesical urinary outflow obstruction were studied in vitro. Urinary outflow obstruction was created by partial ligation of the urethra in female rats. After 10 days a marked hypertrophy of the urinary bladder and a dilatation of the ureters were observed. Proximal and distal segments of the ureters from these animals were isolated and mounted in a wire myograph for force registration. Comparisons were made with ureters from control rats. The ureters from the rats with urinary outflow obstruction exhibited a large increase in lumen diameter and an unchanged thickness of the muscle layer. These data suggest that the dilatation of the ureters is associated with growth of the smooth muscle in the wall. All ureter preparations were relaxed in normal physiological salt solution. When the extracellular K+ concentration was increased to 20 mM the dilated ureters became spontaneously active. At [K+] in the range 20-40 mM in the presence of noradrenaline (10(-5) M) all ureters exhibited high-frequency spontaneous contractions. The dilated ureters had a lower frequency of spontaneous contractions and a higher force. The results show a pronounced remodelling of the ureter wall following infravesical outlet obstruction. The structural changes were associated with alterations in the contraction pattern of the preparations, most probably reflecting changes in the excitation-contraction coupling of the growing cells.

Animals↗

PubMed1995

Major difference between rat and guinea-pig ureter in the ability of agonists and caffeine to release Ca2+ and influence force.

1. We have investigated the internal Ca2+ store and its ability to affect contraction by simultaneously measuring force and Ca2+ in the ureter from guinea-pig and rat. Both species responded in a similar manner to electrical stimulation and depolarization with high-K+, generating plateau-type action potentials and increasing intracellular calcium ([Ca2+]i) and force. 2. In the guinea-pig, carbachol had no effect on [Ca2+]i and force in the resting ureter. In contrast, resting rat ureter always responded with a large [Ca2+]i rise and maintained force to carbachol in Ca(2+)-containing solution, and in Ca(2+)-free solution it showed a transient increase in [Ca2+]i and force. This Ca2+ release and force development was also present in both polarized and high-K(+)-depolarized preparations and was insensitive to nifedipine, suggesting the presence of a receptor-coupled pathway of Ca2+ release in rat ureter. 3. Caffeine was able to produce a release of Ca2+ from the internal store of guinea-pig ureter and elicit contraction. However, rat ureter failed to respond to caffeine. In the presence of La3+, the caffeine response in the guinea-pig ureter and carbachol response in the rat ureter, elicited in Ca(2+)-free solutions, were always increased and prolonged and could be repeatedly evoked, suggesting similarity in Ca2+ uptake behaviour of the store in both species. 4. Ryanodine blocked the caffeine responses of the guinea-pig ureter elicited both in Ca(2+)-containing and Ca(2+)-free solutions, both in the absence and presence of La3+. However, ryanodine failed to prevent the rat ureter responding to carbachol, suggesting that carbachol was releasing Ca2+ from a ryanodine-insensitive channel in the sarcoplasmic reticulum (SR). 5. Cyclopiazonic acid, which inhibits the SR Ca(2+)-ATPase, abolished the effects of both caffeine and carbachol in Ca(2+)-free solutions in guinea-pig and rat, respectively. 6. We conclude that there is a major difference in the mechanisms of Ca2+ release in the internal Ca2+ store of smooth muscle from guinea-pig and rat ureter. The data suggest that the guinea-pig store is purely a calcium-induced calcium release (CICR)-type store and that the rat store is a pure receptor-operated Ca2+ store.

Animals↗

PubMed1991

[Ureteral function at the ureterovesical junction. Action potentials of the canine intramural ureter during bladder filling or bladder contraction].

The relationship between bladder movements and the intramural ureter was studied in the dog by recording electromyograms of the intramural and extravesical ureters recorded during bladder filling and contraction. Bladder filling was achieved by instilling physiological saline at a rate of 10 ml/min to a volume of 5 ml/kg, while bladder contraction was induced by electrical stimulation. For electromyography, an electrode was inserted transperitoneal into both the extravesical ureter and the intramural ureter after it had been separated from the extravesical ureter. A cystostomy for the instillation of water and another cystostomy for the measurement of intravesical pressure were also made in the bladder. During bladder filling at an intravesical pressure of about 10 cmH2O, the frequency of the action potentials in the intramural ureter showed no significant difference to those in the extravesical ureter. In addition, during bladder contraction at a greatly increased intravesical pressure of about 5 times the precontraction level, the frequency of the action potentials in the intramural ureter was not significant by different from those in the extravesical ureter, and also from its own precontraction value. The above findings suggest that action potentials in the intramural ureter are not affected by bladder movements such as filling or contraction, and that the ureter continues to actively transport urine to the bladder during such movements.

Action Potentials↗

PubMedDate not supplied

[Organ-preserving reconstructive operations in reflux into duplicated ureters in children].

A total of 54 children, aged 9 mos--14 yrs were operated on for reflux in double ureters. Out of them 38 patients were with ureter duplex and 16 with ureter fissus in prevesical or intramural area. The surgery was indicated by the reflux, stages III-IV, into a single or both ureters or reflux, stage II, in the patients whose a one-year conservative treatment turned to be a failure. Both segments of morphologically competent kidney were preserved during the reconstructive surgery in 27 patients. Unsatisfactory results of resection and neoimplantation of the both ureters according to Politano-Leadbetter as a "united block" as well as of distal ureteroureteral anastomosis made surgeons abandon the techniques. For the recent 10 yrs the authors have used the Politano-Leadbetter technique of ureteropyelo- or pyelopyelo-anastomosis with the cutting out of the upper segment of the ureter, resection of the distal part of the ureteral low segment and its neoimplantation into the urinary bladder. 20 patients were operated on: 7 with ureter duplex and 13 with prevesical or intramural ureter fissus. Unitype surgery was performed: the resection and implantation of a lower ureter segment: in patients with ureter duplex 7 cm of the distal area was resected, in those with ureter fissus a 2-3-cm resection was made proximately to the site of splitting. The outcomes were followed up for the period of 1 to 9 postsurgical years. The operation turned to be beneficial in 17 patients (85 per cent). In 3 patients nephroureterectomy was performed for the complications arisen: renal hemorrhages (1); the obstruction of vesicoureteral anastomosis (1) and apostematous nephritis (1).(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1988

[Clinical evaluation of vesicoureteroneostomy. I. Efficacy of surgery in 65 cases (100 ureters) of primary vesicoureteral reflux].

We have experienced 72 patients with primary vesicoureteral reflux (VUR) during the past 16 years. Sixty-five of them (100 ureters) were treated surgically to prevent reflux. Among the surgical methods employed, the Politano-Leadbetter method was the most frequent, being used in 56 patients (87 ureters). Other methods were the combined method in 2 patients (three ureters), the Glenn-Anderson method in 1 (2 ureters), the Cohen method in 1 (1 ureter) and the Lich-Gregoir method in 5 patients (7 ureters). As postoperative complications in the early stage (within 1 month after surgery), remaining VUR in 1 ureter in 1 of the patients who underwent surgery by the Politano-Leadbetter method and occurrence of VUR on the contralateral side in 3 patients with unilateral VUR were encountered. These conditions disappeared during the follow-up period. On the other hand, in the late postoperative stage, ureteral stenosis requiring further surgery occurred in 1 ureter in the transitional region to the urinary bladder in 1 patient 2 months after surgery by the Lich-Gregoir method. The rate of success was all 87 ureters (100%) for the Politano-Leadbetter method and 6 out of 7 ureters (85.7%) for the Lich-Gregoir method. The success rates for the other procedures were also good, resulting in an overall rate of 99 out of 100 ureters (99.0%). Ninety-nine percent of the patients had been treated at least once preoperatively for pyelonephritis or fever of unknown etiology. Among these patients, those who had had 5 or more such episodes accounted for 39%.(ABSTRACT TRUNCATED AT 250 WORDS)

Adolescent↗

PubMed1992

Abnormalities in ureter and kidney development in mice given acetazolamide-amiloride or dimethadione (DMO) during embryogenesis.

These experiments more accurately define the effects of the combination acetazolamide-amiloride or a single dose of dimethadione (DMO), the active metabolite of trimethadione, on the development of the ureter. When acetazolamide-amiloride was administered in C57BL/6NCrlBR mice on day 9, 9.5, or 10 of gestation (plug = day 0) a second ureter was formed, anterior to the original ureter, inducing a second kidney. The second ureter then fails to make a connection with the developing bladder and remains attached to the mesonephric duct. The mesonephric duct becomes the vas deferens in the male and deteriorates completely in the female leading to either a restricted ureter or a blocked ureter depending on the sex of the fetus. Administration of a single dose of DMO between gestational day 9 and 10.3 produced both renal agenesis and ureters of varying lengths. Some ureters were of normal length with a tuft of one or two nephrons at their tip, while others were one half or one quarter of their normal length. In some instances the ureter was completely absent. The reason for this strong effect on the ureter is unknown.

Abnormalities, Drug-Induced↗

PubMed2001

Vesical continence in bilateral ectopic single ureters.

PURPOSE: We explore the possibility of gaining suitable vesical capacity and continence in bilateral single ureters without having to resort to urinary diversion or bladder neck reconstruction. MATERIALS AND METHODS: In the last 10 years we treated 6 girls with bilateral ectopic ureters, and 2 with a single kidney and urethral ectopic ureter. Both ureters were ectopic in the urethra in 3 cases, and 1 ureter was inserted in the urethra and 1 in the bladder neck in the other 3. Preoperative examinations included ultrasonography, cystography, excretory urography and endoscopy in all cases, and magnetic resonance imaging in 2. Patient age at intervention ranged from 1 month to 8 years. RESULTS: Cross-trigonal reimplantation of the ectopic ureters through a correctly positioned neomeatus was performed in 7 cases. In 2 patients it was impossible to reach the ureteral insertion from inside the bladder (1 ureter in 1 and both ureters in 1), and so the distal tract of these ureters was resected extravesically as close as possible to the urethra. One patient with a single kidney also had an anorectal malformation and a rectovaginal fistula. She had pelvic renal ectopia and the ureter was inserted beneath the urogenital diaphragm causing minimal bladder capacity. Therefore, a sigmoid neobladder with appendicostomy was constructed according to the Mitrofanoff principle. A Young-Dees bladder neck plasty was done in 2 patients at the same time as ureteral reimplantation and 3 years later in 1. Followup urodynamics revealed more than acceptable continence. Bladder capacity was insufficient in only 1 polyuric patient. CONCLUSIONS: A bladder with bilateral ureteral ectopia is not necessarily useless, and the majority of patients can achieve normal bladder function and capacity along with normal transurethral voiding and satisfactory continence.

Choristoma↗

PubMed2000

Distribution of neuropeptides, histamine content, and inflammatory cells in the ureter.

OBJECTIVES: To determine the anatomic distribution of select neuropeptides (neurokinin A [NKA], substance P [SP], and bradykinin [BK]), of inflammatory cells (leukocytes and mast cells), and the histamine content in the normal swine ureter and compare the findings with regions of increased ureteral contractility. METHODS: Ureters from 10 pigs were obtained and cut into eight segments, proximally to distally. A portion of each ureteral segment was suspended in Krebs buffer (37 degrees C) and attached to force displacement transducers, and spontaneous contractility was measured for 30 minutes. A second portion was assayed for histamine, NKA, SP, and BK using enzyme-linked immunosorbent assay. A third portion was fixed in 10% buffered formalin, stained with hematoxylin-eosin, and evaluated histologically. RESULTS: Ureteral contractility was found to be highest in the most proximal and most distal regions of the ureter. Similarly, SP content was three times greater in the proximal ureter and two times greater in the distal ureter than in the midureter (P <0.05, n = 10). The total NKA and BK content were also higher in the proximal and distal ureter than in the midureter. Conversely, the histamine content was consistent throughout the ureter. Moreover, no significant difference in the distribution of inflammatory cells was identified throughout the ureter. CONCLUSIONS: The anatomic distribution of NKA, SP, and BK in the ureter corresponded to regions of increased spontaneous ureteral contractility, more specifically the proximal and distal ureter. Neuropeptides may play a significant role in ureteral contractility and may be a target for pharmacologic mediation during obstruction and stone passage.

Animals↗

PubMed2006

Cyclooxygenase type 2 is increased in obstructed rat and human ureter and contributes to pelvic pressure increase after obstruction.

Prostanoids exert physiological effects on ureteral contractility that may lead to pressure changes and pain during obstruction. In the present study, we examined whether (1) obstruction changes the expression of the two cyclooxygenase (COX) isoforms, COX-1 and COX-2 in human and rat ureters and (2) administration of a selective COX-2 inhibitor influences the pelvic pressure change after experimental ureteral obstruction. Rats were subjected to bilateral ureter obstruction. Ureters were removed and dissected into a proximal dilated and distal non-dilated segment. RNA and protein were extracted and analyzed for cyclooxygenase expression by quantitative polymerase chain reaction and Western blotting. Human ureter samples were obtained from patients undergoing radical nephrectomy. Rat and human ureteral samples were processed for immunohistochemistry. COX-1, but not COX-2 mRNA, was readily detected in the normal rat ureter. COX-2 mRNA and protein expression was increased in the proximal dilated ureter compared to distal non-dilated ureter. This increased COX-2 expression was associated with increased urinary prostaglandin E2 (PGE2) excretion after release of obstruction. Immunohistochemistry showed increased COX-2 labeling in surface epithelium and smooth muscle layers in both rat and human obstructed ureters compared to control ureters. Furthermore, contractile PGE2-EP1 and thromboxane TP receptors were expressed in ureteral smooth muscle. Systemic treatment with the COX-2 selective inhibitor parecoxib (5 mg/kg/day) attenuated the pelvic pressure increase during obstruction. In summary, COX-2 expression is significantly increased in the ureteral wall in response to obstruction in the rat and human ureter and COX-2 activity contributes to increased pelvic pressure after obstruction.

Animals↗

PubMed1999

Ureteral complications in renal transplantation with more than one donor ureter.

BACKGROUND: The purpose of this study was to evaluate the ureteral complications of renal transplant recipients with more than one donor ureter METHODS: Between 1967 and 1997, 19 patients (median age 34 years, range 6-62 years) received renal transplants from donors with more than one ureter. There were 18 donor organs with two ureters, and one patient underwent en bloc renal transplantation with four donor ureters. In nine patients, the ureters were implanted separately at the bladder dome according to the extravesical technique of Witzel, Sampson, Lich and Röhl. In 10 patients, we performed a modification of this extravesical technique according to Nghiem with a side-to-side anastomosis of the ureters before completing the ureteroneocystostomy. RESULTS: After a median follow-up of 55 months (range 2-218 months), no graft loss due to ureteral complications was noted. One patient died due to myocardial infarction, seven patients returned to dialysis without ureteral complications. There were two patients (one patient after side-to-side ureteral anastomosis, one patient with separate implantation of the two ureters) with ureteral obstruction of one donor ureter. Both patients underwent open surgical revision with temporarily placement of internal ureteral stents. CONCLUSIONS: The presence of multiple ureters from donor kidneys is associated with a higher complication rate in our patient population compared with donor kidneys with one ureter. There was no difference in the long-term outcome between the two implantation techniques used.

Adolescent↗

PubMed1995

Ectopic ureter opening into the seminal vesicle in an infant: a case report and review of the Japanese literature.

A case is presented of an ectopic ureter opening into the seminal vesicle associated with hypodysplastic kidney in an infant. We reviewed 135 cases (139 ureteral units) of male ectopic ureter from the Japanese literature and, of the 139 ectopic ureters, 109 were single-system ectopic ureters, and 26 ureters were associated with the ureteral duplication. Sixty-three and 73 ureters opened into the urinary tract and seminal tract, respectively. In patients 15 years or older, 65 cases of ectopic ureter opened into the seminal tract and 33 cases opened into the urinary tract, whereas in children under 15 years, the ectopic orifice was located more often in the urinary tract (26 cases) than in the seminal tract (8 cases). Presenting symptoms differed according to the location of the ectopic orifice. Ectopic ureters opening into the urinary tract most often presented with urinary tract infection and abdominal or lumbar pain. On the other hand, voiding and ejaculatory symptoms as well as perineal or genital pain were characteristic in ectopic ureters opening into the seminal tract. Of the 83 associated renal segments that were surgically removed, dysplasia, hypoplasia and aplasia were found in 22, 24, 14 cases, respectively. It was noteworthy that 48 of the 53 single ectopic ureters opening into the seminal vesicle were associated with ipsilateral renal dysgenesis.

Choristoma↗

PubMed1994

Effect of cromakalim and glibenclamide on spontaneous and evoked motility of the guinea-pig isolated renal pelvis and ureter.

1. We have investigated the effect of the potassium (K) channel opener, cromakalim, on the spontaneous myogenic activity of the guinea-pig isolated renal pelvis and on myogenic contractions evoked by direct electrical stimulation of the guinea-pig isolated ureter. 2. In the presence of Bay K 8644 (1 microM), electrical stimulation of the guinea-pig ureter (10 Hz for 1 s, pulse width 5 ms, 60 V) produced regular tetrodotoxin-(1 microM) resistant phasic contractions which were suppressed by 3 microM cromakalim. Glibenclamide (0.1-3 microM), 4-aminopyridine (4-AP, 0.1-2 mM) and tetraethylammonium (TEA, 1-10 mM) produced a concentration-dependent inhibition of the effect of cromakalim with the rank order of potency (EC50 in parentheses): glibenclamide (0.64 microM) >> 4-AP (1.11 mM) > TEA (6.6 mM). Apamin (0.1-0.3 microM) was without effect. 3. Cromakalim (0.1-10 microM) produced concentration-dependent inhibition and suppression of spontaneous contractions of the guinea-pig isolated renal pelvis and of evoked contractions of the ureter with EC50 values of 0.71 and 0.47 microM, respectively. 4. Glibenclamide (1 microM) produced a rightward shift of the concentration-response curve to cromakalim in both the renal pelvis and ureter, without producing depression of the maximal inhibitory effect. Glibenclamide did not affect the spontaneous activity of the renal pelvis while it produced a slight enhancement (10-15% increase) of evoked contractions of the ureter. Glibenclamide did not affect the inhibitory action of the adenylate cyclase activator, forskolin, in the renal pelvis or ureter. 5. In electrophysiological experiments (sucrose gap), cromakalim (0.3 and 1 microM) produced hyperpolarization of ureter smooth muscle. Cromakalim also produced a transient suppression of action potentials and accompanying phasic contractions evoked by electrical stimulation. Before suppression of evoked contractions, a shortening of action potential duration was observed concomitant with the developing hyperpolarization produced by cromakalim. A lower concentration (0.1 MicroM) of cromakalim did not affect membrane potential but shortened action potential duration and reduced the evoked contraction.6. Glibenclamide (1 MicroM) inhibited the hyperpolarizing action of cromakalim and prevented its inhibitory action on evoked action potentials and contractions of the ureter. Glibenclamide also produced a slight prolongation of action potential duration and increased the amplitude and duration of the accompanying mechanical response.7. These findings demonstrate that activation of cromakalim- and glibenclamide-sensitive K channels produces a powerful mechanism for regulation of pyeloureteral motility and suppression of latent pacemakers of the ureter in guinea-pig. Glibenclamide-sensitive K channels take part in determining action potential shape and duration in the guinea-pig ureter.

Action Potentials↗