The molecular phenotypes of ureteral telocytes are layer-specific

Telocytes (TC) are the delicate interstitial (stromal) cells defined by their long, thin and moniliform processes termed telopodes. Numerous studies determined that different subsets of telocytes populate almost all tissues and attempted to relate these subsets to various functions, from cell signaling to tissue repair and regeneration. Extremely few studies addressed the urinary tract though few data on the molecular pattern of the urinary TCs actually exist. We therefore hypothesized that subsets of urinary TCs co-localize within the human ureter and we aimed at performing an immunohistochemical study to evaluate the tissue-specific molecular pattern of TCs. On sample tissues of proximal ureter drawn from ten human adult patients during surgery were applied primary antibodies against CD34, CD105, von Willebrand Factor, the heavy chain of smooth muscle myosin (SMM) and c-erbB-2. The molecular pattern indicated three different subsets of ureteral TCs which are neither endothelial nor epithelial in nature: (a) type I: the CD34-/CD105+ TCs of the superficial layer of lamina propria; (b) type II: the CD34+/CD105± myoid TCs of the deep layer of lamina propria and (c) type III: the CD34+/CD105+ perivascular TCs. Although apparently different, all these subsets of TCs could belong to the stem/progenitor niche of the ureter.

Does the histopathologic pattern of the ureteropelvic junction affect the outcome of pyeloplasty

PURPOSE

To investigate the effects of the histopathologic pattern of obstructed ureteropelvic junction (UPJ) specimens, including collagen type 3, elastin, fibrosis and Cajal cells, on the outcome of pyeloplasty.

MATERIALS AND METHODS

Histopathological specimens obtained following Anderson-Hynes pyeloplasty from 52 patients with intrinsic ureteropelvic junction obstruction (UPJO) between January 2005 and January 2008 were evaluated histopathologically. Patients with extrinsic or secondary UPJO were excluded. Preoperative and postoperative radiographic evaluations were performed either via diuretic renography or intravenous pyelography, or both. Six months post-surgery the patients were divided into 2 groups, as successful surgery (group 1) and unsuccessful surgery (group 2). Histopathological findings (collagen type 3, elastin, fibrosis and Cajal cells) in each group were statistically compared.

RESULTS

The study included 52 patients (21 female and 31 male). Mean age of the entire study population was 39.42 ± 14.5 years, versus 39.63 ± 14.9 years in group 1 (n = 47) and 37.4 ± 10.0 years in group 2 (n = 5). Median follow-up was 18 months. There weren't any significant differences in collagen type 3, elastin, fibrosis, or Cajal cells between the 2 groups (P > .05).

CONCLUSION

The histopathologic pattern of UPJ was not a factor associated with the success of pyeloplasty. Based on the present findings, we conclude that surgical technique is more important than the histopathologic pattern of UPJ for the successful treatment of UPJO.

Aberrant differentiation of urothelial cells in patients with ureteropelvic junction obstruction

AIM

To investigate the urothelial changes in the pathogenesis of ureteropelvic junction obstruction (UPJ-O).

METHODS

A total of 12 patients of UPJ-O were respectively studied. The expression of Annexin A7, Annexin A11, EGFR, Keratin 5, uroplakin III, and SMA in the urothelium of obstructed UPJ segment and of the normal ureter below the obstructed segment were determined by immunofluorescence. Transmission electron microscopy was used to determine the morphological changes in UPJ epithelium in compared to normal ureteral epithelium.

RESULTS

We found that Annexin A7, Annexin A11, EGFR, Keratin 5, and SMA were upregulated, while uroplakin III was downregulated in the urothelium of UPJ-O patients. Furthermore, ultrastructural analyses showed that intercellular spaces between urothelial cells were dilated and the number of microvilli on superficial cells was increased in UPJ-O patients.

CONCLUSIONS

We propose that a disrupted urothelial barrier in UPJ-O may results in urothelial inflammatory response and truncated differentiated urothelial cells, which may play an important role in the development and pathogenesis of UPJO.

Distribution of cocaine and amphetamine regulated transcript in ureters and urinary bladder of hypertensive rats

Cocaine and amphetamine regulated transcript (CART), a neuropeptide of the central and peripheral nervous system plays an essential role in maintaining body homeostasis by regulating body temperature, orexia, digestive motility and blood pressure. Very few studies describe the relationship of hyperten¬sion with CART. Therefore, the present research was undertaken to identify, locate and determine the number of CART-immunopositive neuroendocrine cells (NE) and structures in the urinary bladder and ureter of rats with experimentally induced nephrogenic hypertension. The experiments were conducted on 20 Wistar rats in which hypertension was experimentally induced by applying a clamp on the left renal artery based on the two kidney, one clip experimental model (2K1C). After 6 weeks, fragments of the ureters and urinary bladder were sampled from rats with permanent hypertension. Immunohisto¬chemical analyses revealed a salient effect of renovascular hypertension on the neuroendocrine system of rat ureters and urinary bladder. Differences in the number of neuroendocrine cells and in the density of CART-positive structures were identified between the hypertensive and normotensive (control) rats. Hypertension greatly increased the number of NE cells and the density of CART- immunoreactive (IR) structures in the analysed urinary system organs.

In vitro effects of PDE5 inhibitors sildenafil, vardenafil and tadalafil on isolated human ureteral smooth muscle: a basic research approach

Cyclic nucleotide phosphodiesterase (PDE) isoenzymes are key proteins regulating intracellular cyclic nucleotide turnover and thus smooth muscle tension. Several in vitro studies have indicated that the cyclic GMP and cyclic AMP-mediated signaling may play a role in the control of human ureteral muscle. The aim of the present study was to evaluate the functional effects of PDE5 inhibitors sildenafil (Sil), vardenafil (Var) and tadalafil (Tad), as well as nitric oxide (NO)-donating agent sodium nitroprusside (SNP) and non-selective muscarinic antagonist butylscopolamine (BSC) on the tension induced by KCl and the turnover of cyclic nucleotides in isolated human ureteral smooth muscle. In vitro relaxant responses of human ureteral smooth muscle to the PDE5 inhibitors mentioned above were investigated using the organ bath technique. Cyclic nucleotides cAMP and cGMP were determined by means of specific radioimmunoassay following incubation of the tissue with Sil, Var, Tad and SNP. The tension induced by KCl of the ureteral tissue was dose dependently reversed by the drugs with the following rank order of efficacy: SNP > Var >or= Sil > Tad > BSC. R(max) values ranged from 25 +/- 9% (SNP) to 5 +/- 3% (BSC). Relaxant responses were paralleled by threefold to fourfold increase in tissue levels of cGMP. Our results indicate that PDE5 inhibitors can reverse the tension of isolated human ureteral smooth muscle via cGMP-mediated pathways. Nevertheless, further studies are indicated in order to evaluate as to whether there might be a use for PDE5 inhibitors in the treatment of ureteral stone disease.

[Reactive transformation of human urinary smooth muscular tissue in some diseases (structural-metabolic aspects of organization)]

Smooth muscular tissue (SMT) of human urinary system was studied at different levels (renal pelvis, proximal and distal parts of the ureter) in health and some urological diseases (vesicoureteral reflux, ureteral obstruction). The method of target cell dissociation was used. The volume of myocytes, nuclei, nuclear-cytoplasmic correlation were calculated. Content of DNA and cytoplasmic protein was studied cytospectrophotometrically. Electron-microscopic study was also made. Three types of myocytes with different structural-metabolic parameters were detected. There were significant differences in mean volumes of myocytes, cytophotometric indices of SMT in different parts of the urinary tracts related to the pattern of these zones functioning. A comparative analysis of intact and affected SMT of the distal ureter demonstrated changes in the structure of leiomyocytes population, optic density of cytoplasmic protein and proliferative activity of myocytes which correlated depending on the kind and change of functional load.

H-Ras, R-Ras, and TC21 differentially regulate ureteric bud cell branching morphogenesis

The collecting system of the kidney, derived from the ureteric bud (UB), undergoes repetitive bifid branching events during early development followed by a phase of tubular growth and elongation. Although members of the Ras GTPase family control cell growth, differentiation, proliferation, and migration, their role in development of the collecting system of the kidney is unexplored. In this study, we demonstrate that members of the R-Ras family of proteins, R-Ras and TC21, are expressed in the murine collecting system at E13.5, whereas H-Ras is only detected at day E17.5. Using murine UB cells expressing activated H-Ras, R-Ras, and TC21, we demonstrate that R-Ras-expressing cells show increased branching morphogenesis and cell growth, TC21-expressing cells branch excessively but lose their ability to migrate, whereas H-Ras-expressing cells migrated the most and formed long unbranched tubules. These differences in branching morphogenesis are mediated by differential regulation/activation of the Rho family of GTPases and mitogen-activated protein kinases. Because most branching of the UB occurs early in development, it is conceivable that R-Ras and TC-21 play a role in facilitating branching and growth in early UB development, whereas H-Ras might favor cell migration and elongation of tubules, events that occur later in development.

ELASTIN CONTENT OF THE RENAL PELVIS AND URETER DETERMINES POST-PYELOPLASTY RECOVERY

PURPOSE

We evaluated the collagen-to-smooth muscle tissue matrix ratio and percentage of elastin in the renal pelvis, ureteropelvic junction (UPJ) and ureter, and compared these findings with the degree of obstruction, patient age and post-pyeloplasty renal recovery.

MATERIALS AND METHODS

We analyzed histological sections from 75 patients with UPJ obstruction. Nine patients were excluded owing to bilateral UPJ obstruction and an improper specimen. We divided the specimen obtained from pyeloplasty into 3 parts, namely the renal pelvis above the obstruction, the obstructed UPJ portion and the ureter below the obstruction. To examine the collagen and smooth muscle, sections were stained using Masson's trichrome, and elastic van Giesson stain was used for elastin, smooth muscle and collagen. Collagen, smooth muscle and elastin populations were identified, and the tissue matrix ratio and percentage of elastin were calculated by color image analysis.

RESULTS

In patients with lower ratios of collagen-to-smooth muscle in the UPJ proper hydronephrosis was more improved postoperatively (p = 0.049). In patients with a lower percentage of elastin in the renal pelvis, UPJ and ureter hydronephrosis was more improved postoperatively (p <0.0001).

CONCLUSIONS

Because the UPJ portion was resected during pyeloplasty, the renal pelvis and the ureter remaining after pyeloplasty are likely to be related to improved hydronephrosis. A higher percentage of elastin in the renal pelvis and ureter contributes to inelasticity and low compliance, and results in a slower recovery from hydronephrosis after pyeloplasty.

Different adhesion and migration properties of human HCV29 non-malignant urothelial and T24 bladder cancer cells: role of glycosylation

In tumour cells, alterations in cellular glycosylation may play a key role in their metastatic behaviour. This study used cell lines having very different behaviour in vivo: HCV29 non-malignant transitional epithelium and T24 bladder transitional cell carcinoma. These differences in behaviour might be due in part to differences in cellular glycosylation patterns. Glycan chain analysis of their glycoproteins was performed with the use of specific lectins. The functional role of carbohydrates was studied by treating these cells with swainsonine, an inhibitor of Golgi alpha-mannosidase II, and in vitro adhesion and migration assays. The adhesion of swainsonine-treated HCV29 and T24 cells was increased on fibronectin and type IV collagen by 1.5- and 2-fold, respectively, whereas adhesion on laminin was virtually unchanged after swainsonine-treatment in HCV29 cells and was increased in T24 cells. Swainsonine treatment reduced the rate of T24 cell migration by 20%. We concluded that beta1-6 branched tri- and tetraantennary complex-type glycans have an important function in adhesion and migration in the studied cell lines. These data support the view that oligosaccharides are involved in several steps of the metastatic process.

Expression of the hMLH1 and hMSH2 proteins in normal tissues: relationship to cancer predisposition in hereditary non-polyposis colon cancer

The majority of tumours in patients with hereditary non-polyposis colon cancer (HNPCC) occur in large intestine and endometrium; also, other tissues are at increased risk. We studied expression of hMLH1 and hMSH2 proteins in 148 normal samples of various tissues from non-HNPCC patients and in 14 normal colon tissues from HNPCC patients. Immunohistochemical technique was used. Intensity of nuclear staining, percentage of stained cells and H-scores were calculated. Tissues were divided into groups. Groups A, B and C included tissues with increased risk of cancer in HNPCC A) stomach, small and large bowel; (B) endometrium; (C) ovary, ureter, urinary bladder, kidney and liver. Group D tissues were without increased risk. Expression of the proteins was significantly higher in groups A, B and C compared with group D (P<0.0001, P=0.0004 for hMSH2 in C versus D). The expression was highest in testis. In colons of HNPCC patients, expression of the mutated gene product was significantly lower than in non-HNPCC patients. In conclusion, hMLH1/hMSH2 protein expression is constitutively higher in certain cell types of certain tissues, including the majority of tissues that are at increased risk of cancer in HNPCC. However, association of strong hMLH1/hMSH2 expression with cancer risk is not strictly valid.

[The uteropelvic junction in children: from the clinical problems to the morphogenetic approach]

The responsibility of the uteropelvic junction (UPJ) syndrome or abnormalities for renal affections and also for high obstructive uropathy is well-known. But, controversies still remain about the anatomic approach of this clinical feature. Our purpose is to elucidate the developmental anatomy of UPJ and eventually to set the steps of the anatomic approach of the UPJ abnormalities. This study also leads to a better understanding of the mechanism of the intrinsic ureteropelvic junction obstructions. A total number of 122 post-mortem specimens with ages ranging from 1 day to 30 months in both sexes underwent formalin treatment for histological investigation. We performed both transverse and longitudinal sections. Hematein-eosin-safran and Masson's trichrome staining were used. Histological examination revealed that myoarchitecture of UPJ set increasingly up. Circular muscle fibers were first to put in. They had an initial arrangement as a ring in neonates and infants. We conclude that circular layer appears first and sooner than others. On the other hand, coincidence in time between ages of our specimens and ages of patients sufferning from UPJ syndrome leads to further investigations to determine the implication of ring-shaped circular layer in intrinsic ureteropelvic junction obstruction.

EXTRACELLULAR MATRIX DEGRADATION AND REDUCED NERVE SUPPLY IN REFLUXING URETERAL ENDINGS

PURPOSE

Extracellular matrix (ECM) degrading enzymes and the nerve supply of the ureterovesical junction were investigated using immunohistochemical methods to gain insight into the pattern of refluxing ureteral endings.

MATERIALS AND METHODS

Specimens were obtained from ureterorenal units of 36 children undergoing reflux surgery with a mean age of 62.5 months and 9 age matched controls without reflux. Routine histological paraffin embedded sections were stained for general morphology. Indirect immunohistochemical methods assessing matrix metalloproteinase 1 were used to study the intensity of matrix turnover, and activated macrophage marker CD68 was quantified to describe scavenging of damaged ECM. The intramural neuronal network was explored using nerve specific immunoperoxidase for S-100 protein.

RESULTS

Refluxing ureteral endings demonstrated structural deficiencies of the smooth muscle wrap associated with a 3.8-fold increase of cellular matrix metalloproteinase 1 production and a significant increase of CD68+ macrophages, respectively. The S-100 pattern yielded significant diminution. Lacking B and T lymphocytes in the ECM precluded chronic inflammation.

CONCLUSIONS

Refluxing ureteral endings showed a pathologically increased matrix remodeling combined with deprivation of the intramural nerve supply. Macrophage activation referring to altered morphology was represented by an increased expression of CD68 at the sites of increased ECM turnover.

Healing process in the ureter: an experimental study in dogs

OBJECTIVE

This study set out to describe the basic milestones in the pattern of healing in the ureter in order to understand why problems in healing arise when the ureter is severed, usually through anastomotic leakage or stricture formation.

METHOD

Transection and anastomosis of the ureter were performed on dogs. The anastomotic segment was removed at days 6, 14, 21 and 42. Mucopolysaccharide levels, collagen content and breaking strength were measured on these samples and on anatomically similar segments from normal dogs. A minimum of five observations were carried out at each time point. The mean values of the estimations in various groups were compared. Differences were considered significant at p < or = 0.05.

RESULTS

Mucopolysaccharide levels peaked at day 6 and then fell gradually to near normal (p > 0.05) by day 42. The collagen content rose to a maximum at day 14 and then fell to near normal levels (p > 0.05) by day 21. Breaking strength rose gradually to peak by day 21 and then fell to reach day 6 level (> 0.05) at day 42. At no time point did it reach anywhere near normal value. Full healing in the ureter takes at least six weeks.

CONCLUSION

The healing process in the injured ureter is different to that in other tissues. It is probable that clues to anastomotic healing problems of the ureter lie in the paradoxical pattern of collagen formation.

Altered expression of interstitial cells of Cajal in congenital ureteropelvic junction obstruction

PURPOSE

Peristaltic contractions in the upper urinary tract serve to move urine from the kidney through the ureter to the bladder. Ureteropelvic junction (UPJ) obstruction is the most common cause of congenital hydronephrosis in children. To our knowledge the pathophysiology of UPJ obstruction is unknown. C-kit positive interstitial cells of Cajal (ICCs) are pacemaker cells that facilitate active propagation of electrical events and mediate neurotransmission. We investigated the expression of c-kit positive cells in the muscle layer of normal and obstructed UPJ specimens.

MATERIALS AND METHODS

A total of 19 human formalin fixed, paraffin embedded specimens of intrinsic UPJ obstruction from children with a mean age of 2.3 years (range 2 months to 12 years) and 7 control samples from children with a mean age of 4.5 years (range 11 months to 9 years) were investigated immunohistochemically for the expression of c-Kit oncoprotein and peripherin by light and laser scanning microscopy. Quantification of immunolabeled structures was quantified using computerized image analysis.

RESULTS

Peripherin immunoreactivity was strong in the muscle layer of normal UPJ specimens, while in UPJ obstructed specimens there was a decrease in peripherin positive nerve fibers. In normal UPJ specimens there were many c-Kit positive ICCs between the muscle bundles. The density of ICCs was markedly decreased in the muscle layers of UPJ obstructed specimens.

CONCLUSIONS

To our knowledge this study shows for the first time the immuno-expression of c-Kit positive ICCs in the proximal part of the normal human upper ureter. The altered density of c-Kit positive cells in UPJ obstruction may have a role in the failure of transmission of peristaltic waves across the UPJ.

The Intravesical Ureter in Children With Vesicoureteral Reflux: A Morphological and Immunohistochemical Characterization

PURPOSE

We investigated intravesical ureteral endings using immunohistochemical methods to study general morphology, smooth muscle architecture and collagen composition in children with vesicoureteral reflux.

MATERIALS AND METHODS

Samples were obtained from 29 ureterorenal units in children with a mean age of 52.3 months undergoing reflux surgery. Routine histological paraffin embedded sections were stained with hematoxylin and eosin, and Masson trichrome to assess general morphology. Staining for actin, myosin and desmin was performed to evaluate the presence, allocation and architecture of the ureteral smooth muscle wrap. In addition, indirect immunohistochemical methods were used to study the collagen composition of the ureteral wall and CD68 was used for macrophage labeling as a marker of tissue remnant scavenging. All investigations were done using high power field magnification for quantification. In addition, age matched, nonrefluxing ureteral specimens served as controls.

RESULTS

Smooth muscle alpha-actin, myosin and desmin expression were extensively decreased in all specimens pertaining to the ureteral ending. This distal part showed a high degree of muscle atrophy and degeneration as well as a disordered fiber arrangement associated with increased extracellular matrix collagen accumulation. In addition, CD68 positive macrophages were significantly increased. In contrast to these observations, the proximal intravesical portion of the ureter showed intact morphology and arrangement of the muscular coat.

CONCLUSIONS

Refluxing intravesical ureteral endings showed dysplasia, atrophy and architectural derangement of smooth muscle fibers. Consequently symmetrical contraction of the distal ureteral smooth muscle coat creating the active valve mechanism to protect reflux is not achievable.

The structure of the oligosaccharides of alpha3beta1 integrin from human ureter epithelium (HCV29) cell line

There is a growing line of evidence that glycosylation of alpha and beta subunits is important for the function of integrins. Integrin alpha3beta1, from human ureter epithelium cell-line HCV29, was isolated by affinity chromatography on laminin GD6 peptide. Characterization of its carbohydrate moieties was carried out using sodium dodecyl sulfate/polyacrylamide gel electrophoresis followed by Western blotting on Immobilon P and on-blot deglycosylation with peptide N-glycosidase-F. Profiles of N-glycans for each subunit were obtained by matrix-assisted laser desorption/ionization mass spectrometry. Our findings demonstrated, in both subunits of integrin alpha3beta1, the presence of complex type oligosaccharides with a wide heterogeneity. Bi- tri- and tetraantennary structures were the most common, while high-mannose type structures were minor. Also the presence of short poly-N-acetyllactosamine entities was shown. These results show that while the predominant oligosaccharides of both subunits are identical, some slight differences between them do exist.

Caspase-9 takes part in programmed cell death in developing mouse kidney

Programmed cell death is a mechanism by which organisms dispose of unwanted cells, and it is thought to be an important process in organogenesis. We have already reported the role of caspase-3 in the developing metanephros. While caspase-3 is thought to be positioned downstream of the caspase-activating cascade, the upstream caspase for programmed cell death in the developing kidney is still unknown. In an attempt to identify it, we blocked caspase activity in metanephric explants with caspase inhibitors. Administration of a caspase-9 inhibitor (Ac-IETD-CHO) effectively prevented both ureteric bud branching and nephrogenesis, the same as a caspase-3 inhibitor (Ac-DEVD-CHO). On the other hand, administration of a caspase-8 inhibitor (Ac-LETD-CHO) did not inhibit ureteric bud branching or nephrogenesis. Apaf-1, which executes programmed cell death in the caspase-9-related pathway, was detected in the cells exhibiting caspase-9 activity, and our results suggest that Apaaf-1/caspase-9 activates caspase-3 in kidney organogenesis.

[The differentiation of rhythmogenic characteristics of the ureter's different regions in guinea pigs]

Characteristics of rhythmogenic pacemakers of the ureter's perirenal middle and peribladder region morphologically and electrophysiologically are analysed in guinea pigs both in presence of spreading activity and breach of conductivity. It was shown that the action potential's amplitude of the middle region is the highest and duration of the spike activities from perirenal zone is maximal and all three regions are characterised by different functional conditions.

Expression, localization, and regulation of aquaporin-1 to -3 in rat urothelia

Although mammalian urothelia are generally considered impermeable to constituents of urine, in vivo studies in several species indicate urothelial transport of water and solutes under certain conditions. This study investigates the expression, localization, and regulation of aquaporin (AQP)-1, -2, and -3 in ureteral and bladder tissues in 48-h dehydrated and water-loaded female Wistar rats. Immunoblots of homogenates of whole ureter and bladder identified characteristic approximately 28- and 35- to 44-kDa bands for AQP-1, -2, and -3. AQP-1 was localized to capillary and arteriole endothelial cells, whereas AQP-2 and -3 circumferentially lined the epithelial cell membranes except for the apical membrane of the epithelial cells adjacent to the lumens of both ureter and bladder. AQP-2 was also present in epithelial cell cytoplasm. Dehydration resulted in 160-200% increases of AQP-3 signal and 24-49% increases of AQP-2 signal but no change in AQP-1 signal on immunoblots of homogenates of ureters and bladders. AQPs in genitourinary tract urothelia likely play a role in the regulation of epithelial cell volume and osmolality and may play a role in bulk water movement across urothelia.

Pituitary adenylate cyclase activating peptide (PACAP) immunoreactivity in the ureter of the duck

The presence, distribution and colocalisation of pituitary adenylate cyclase activating peptide (PACAP) immunoreactivity have been studied in the duck ureter by using Western blot analysis, radioimmunoassays (RIA) and immunohistochemistry. The presence of both PACAP-38 and PACAP-27 was demonstrated, PACAP-38 being the predominant form. PACAP-immunoreactive fibres and neurons were found in all the ureteral layers. Double immunostaining showed that PACAP was almost completely colocalised with vasoactive intestinal peptide (VIP). Moreover, PACAP was found in substance P (SP)-containing ureteral nerve fibres and in SP-containing dorsal root ganglion neurons. RIA performed on denervated ureters demonstrated that almost half of the ureteral PACAP was extrinsic in origin. These findings suggest that, in birds, PACAP has a role in diverse nerve-mediated ureteral functions.

The C5a receptor is expressed by human renal proximal tubular epithelial cells

The C5a receptor is expressed by a variety of cell types. These studies demonstrate by immunohistochemistry that the receptor is present on the surface of proximal and distal tubular epithelial cells from normal kidney. In addition, the receptor was detected on transitional epithelial cells of the ureter and bladder. Primary proximal tubular cultures and a proximal tubular cell line both also expressed the C5a receptor, as demonstrated by immunofluorescence and by FACS analysis. The presence of mRNA encoding the receptor was confirmed by reverse transcriptase-polymerase chain reaction analysis. As opposed to its effect on glomerular mesangial cells, the receptor did not mediate a proliferative response by the proximal tubular cells. C5a also did not enhance the synthesis/secretion of transforming growth factor-beta 1, monocyte chemoattractant protein-1, platelet-derived growth factor-AB or tumour necrosis factor-alpha by cultured proximal tubular cells. Therefore, although the C5a receptor clearly is expressed by proximal tubular cells, clarification of its functional relevance on this cell type awaits further studies.

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.

The distribution of vesicular acetylcholine transporter in the human male genitourinary organs and its co-localization with neuropeptide Y and nitric oxide synthase

Because doubt still remains concerning the distribution of nerves that are unequivocally cholinergic in the human genitourinary organs, we have used a specific marker, namely, an antibody to vesicular acetylcholine transporter (VAChT), to immunolabel cholinergic axons and cell bodies in specimens of urinary bladder, seminal vesicle, vas deferens, and prostate gland obtained from neonates and children post mortem. In addition some sections were double-immunolabeled with VAChT and either neuropeptide Y (NPY) or nitric oxide synthase (NOS). The results demonstrated a rich cholinergic innervation to the muscle coat of the bladder body with a much less prominent, but nonetheless significant, cholinergic innervation to the smooth muscle components of the seminal vesicle, vas deferens, and prostate. Small ganglia were scattered throughout the detrusor muscle of the urinary bladder, approximately 75% of the intramural neurons being VAChT immunoreactive, whereas approximately 95% contained NPY and approximately 40% contained NOS. VAChT immunoreactivity was observed in 40% of neurons in ganglia scattered throughout the pelvic plexus. Almost all these cholinergic neurons contained NPY and approximately 65% contained NOS. Almost all the cholinergic nerve fibers throughout the genitourinary organs also contained NPY. Although NOS was sparse in the cholinergic nerves of the bladder body, it occurred in the majority of cholinergic nerves at the bladder neck and was also present in a proportion of the cholinergic nerves in the other organs examined. VAChT-immunoreactive nerves were also observed in a sub-epithelial location in all the organs examined, the majority containing NPY, whereas a small proportion contained NOS. Although doubt remains about the function of sub-epithelial cholinergic nerves in the urinary bladder, the majority of similar nerves in the seminal vesicle, vas deferens, and prostate gland are considered to be secretomotor. Collectively these findings demonstrate that the cholinergic innervation of the male genitourinary system is well established in the neonate and child. Neurourol. Urodynam. 19:185-194, 2000.

The effects of beta-adrenoceptor agonists on KCl-induced rhythmic contraction in the ureter of guinea pig

In the present study, we tried to determine what effects were induced by beta-adrenoceptor agonists on 40 mM KCl-induced rhythmic contraction and to clarify which beta-adrenoceptor subtypes are involved in the regulation of ureter motility in the guinea pig by using in vitro functional analysis. 40 mM KCl-induced rhythmic contraction was abolished by papaverine (10(-6) M), nicardipine (10(-5) M) and cromakalim (10(-5) M), but was not influenced by atropine (10(-6) M). Isoprenaline decreased the amplitude, and changed the pattern of 40 mM KCl-induced rhythmic contraction in concentration-dependent manner. These results suggest the possibility that the stimulation of beta-adrenoceptors may regulate the ureteral peristalsis. Salbutamol (selective beta2-AR agonist) and CGP12177 (beta(1,2)-AR antagonist and beta3-AR partial agonist) were also effective in decreasing the amplitude and changing the pattern of the rhythmic contraction. The pD2 values of agonists were 7.57 (isoprenaline), 5.80 (CGP12177) and 7.63 (salbutamol), respectively. The concentration-response curves of isoprenaline and salbutamol were rightward shifted by the presence of propranolol, and the apparent pA2 values for propranolol against isoprenaline and salbutamol were 7.12 and 6.29, respectively. These results suggest that inhibition for 40 mM KCl-induced rhythmic contraction of the ureter by isoprenaline and salbutamol mediated mainly via atypical beta-adrenoceptor subtype.

Aristolactam I a metabolite of aristolochic acid I upon activation forms an adduct found in DNA of patients with Chinese herbs nephropathy

Aristolochic acid (AA) a naturally occuring nephrotoxin and carcinogen is implicated in a unique type of renal fibrosis, designated Chinese herbs nephropathy (CHN). We identified AA-specific DNA adducts in kidneys and in a ureter obtained from CHN patients after renal transplantation. AA is a plant extract of aristolochia species containing AA I as the major component. Aristolactams are the principal detoxication metabolites of AA, which were detected in urine and faeces from animals and humans. They are activated by cytochrome P450 (P450) and peroxidase to form DNA adducts. Using the 32P-postlabelling assay we investigated the formation of DNA adducts by aristolactam I in these two activation systems. A combination of two independent chromatographic systems (ion-exchange chromatography TLC and reversed-phase HPLC) with reference compounds was used for the identification of adducts. Aristolactam I activated by peroxidase led to the formation of several adducts. Two major adducts were identical to adducts previously observed in vivo. 7-(deoxyguanosin-N2-yl)aristolactam I (dG-AAI) and 7-(deoxyadenosin-N6-yl)aristolactam I (dA-AAI) were formed in DNA during the peroxidase-mediated one-electron oxidation of aristolactam I. Aristolactam I activated by P450 led to one major adduct and four minor ones. Beside the principal AA-DNA adducts identified recently in the ureter of one patient with CHN, an additional minor adduct was detected, which was found to have indistinguishable chromatographic properties on TLC and HPLC from the major adduct formed from aristolactam I by P450 activation. Thus, this minor AA-adduct might be evolved from the AAI detoxication metabolite (aristolactam I) by P450 activation. These results indicate a potential carcinogenic effect of aristolactam I in humans.

Endopyelotomy failure is associated with reduced transforming growth factor-beta

PURPOSE

Approximately 15% of patients with ureteropelvic junction obstruction have endopyelotomy failure and require an additional surgical procedure to remove the obstruction. Transforming growth factor-beta (TGF-beta), a cytokine which stimulates mesenchymal cell proliferation and extracellular matrix deposition, increases in the renal pelvis in response to obstruction. However, TGF-beta also is implicated in smooth muscle regeneration and wound healing. To understand the pathophysiology of ureteropelvic junction obstruction and determine why endopyelotomy fails in some obstructed ureteropelvic junctions, TGF-beta expression in obstructed and normal ureteropelvic junction segments was compared.

MATERIALS AND METHODS

Immunohistochemical staining using a rabbit polyclonal anti-TGF-beta was performed on deparafinfized 4 microm. sections of paraffin blocked ureteropelvic junction segments. Human obstructed ureteropelvic junction segments were removed during primary pyeloplasties (11) and secondary pyeloplasties after endopyelotomy failure (11). Normal ureteropelvic junction segments were removed during nephrectomy for purposes unrelated to obstruction (11). Grading on a scale of 0 to 4 was performed by a physician blinded to the source of the specimen.

RESULTS

Mean TGF-beta expression plus or minus standard error of the mean was significantly increased (p <0.02) in obstructed ureteropelvic junctions from primary pyeloplasties (2.6+/-0.7) compared to normal ureteropelvic junctions (1.6+/-0.7), as expected. However, TGF-beta expression in the endopyelotomy failure group (1.8+/-0.6) was not significantly different from that in normal ureteropelvic junctions and was significantly lower (p <0.05) than that in obstructed ureteropelvic junctions from primary pyeloplasties.

CONCLUSIONS

Obstructed ureteropelvic junctions in cases of endopyelotomy failure have decreased expression of TGF-beta compared with other obstructed ureteropelvic junctions. These data suggest that an elevation of TGF-beta in obstructed ureteropelvic junctions may be necessary for successful tissue repair after endopyelotomy.

In vitro ligation of ureters and urethra modulates fetal mouse bladder explants development

The compliance of the bladder which accommodates the holding and voiding of urine is influenced by the amount and type of collagen deposited as well as the packing and organization of collagen fiber bundles. During fetal development, the accumulation of urine within the bladder lumen is associated with the maturation of the bladder's wall. Fetal mouse bladders can undergo maturation as organ cultured explants in defined medium. Polarized light optics of Sirius red-stained sections of fetal mouse bladders in organ culture for 4 days showed that the ligation of both ureters and urethra promoted more orderly packing of collagen fiber bundles within the luminal edge of the lamina propria compared to unligated bladder explants. It is proposed that ligation causes differences in the development and organization of the collagen fiber bundles within the bladder wall. These differences are due to either increases in intravesical pressure, the accumulation of growth factors within the lumen or a combination of both.

Chloride channels ClC-2 and ICln mRNA expression differs in renal epithelial ontogeny

Development-dependent mRNA expression of the chloride channels ClC-2 and ICln was studied by quantitative reverse transcriptase-polymerase chain reaction in rat ureteric bud and cortical collecting duct primary monolayer cultures. Abundance of ClC-2 mRNA increased in ureteric bud cells between embryonic day 15 (E15) and E17, peaked at postnatal day 3 (P3), and was down-regulated at P7 when morphogenesis is complete, suggesting a specific embryonic function. Expression of ICln mRNA, in contrast, up-regulated continuously with development.

A quantitative histologic analysis of collagen subtypes: the primary obstructed and refluxing megaureter of childhood

OBJECTIVES

To analyze and identify collagen subtypes in the primary obstructed and refluxing megaureter of childhood.

METHODS

Anticollagen monoclonal antibodies to collagen types I, III, and IV were used in control ureters (n = 4), obstructed (n = 7), and refluxing (n = 13) megaureters. Additionally, all were stained with Masson's trichrome to further define the extracellular matrix. After staining and serial sectioning, representative ureteral sections, focusing on the muscularis and lamina propria regions, were digitized and analyzed with a color image analysis system.

RESULTS

Immunohistochemical studies demonstrated increases in collagen types I and III for both obstructed and refluxing megaureters compared with controls (P <0.05). Collagen type IV was not detected in statistically significant amounts in any ureter. In control ureters most was type I (83% +/- 9%) collagen. Obstructed megaureters produced similar results with virtually all collagen being type I (84% +/- 26%) with very little type III collagen present, 5.3% +/- 3%. Refluxing megaureters contained only 55% +/- 15% type I collagen. However, there was an increase in type III collagen (16% +/- 4%) versus (4.5% +/- 2%) in controls (P <0.05).

CONCLUSIONS

These data suggest that the greater contribution of type III collagen may play a role in the pathophysiology of refluxing megaureters. Because type III collagen is a less distensible fiber, it may cause an intrinsically stiffer ureter and play a role in the lower surgical success in the reimplantation of refluxing megaureters.

Prognostic significance of Ki-67 labeling index in urothelial tumors of the renal pelvis and ureter

PURPOSE

We evaluated the prognostic significance of the Ki-67 labeling index in 70 patients with primary urothelial tumors of the renal pelvis and ureter.

MATERIALS AND METHODS

Immunohistochemical staining for Ki-67 in archival tumor materials was done by the streptavidin-biotin method.

RESULTS

Univariate survival analysis showed that the prognosis of patients with a high Ki-67 labeling index of 21.7 or more was significantly worse than that of patients with an intermediate labeling index of 13.3 to less than 21.7 (p < 0.01) or a low labeling index of less than 13.3 (p < 0.001). Multivariate survival analysis showed that staining for Ki-67 labeling index was significantly correlated with prognosis (p < 0.01).

CONCLUSIONS

Analysis of Ki-67 labeling index provides useful prognostic information about patients with primary urothelial tumors of the renal pelvis and ureter.

Simultaneous left renal pelvic and bilateral ureteral tumors producing carbohydrate antigen 19-9

We report a case of a transitional cell carcinoma of the left renal pelvis and both ureters which secreted carbohydrate antigen 19-9. Aggressive surgery was performed including a left nephroureterectomy including the bladder cuff and a right total ureterectomy with an ileal graft replacement. The patient has had good kidney function and no evidence of disease for one year postoperatively.

Blood group glycosphingolipid expression in kidney of an individual with the rare blood group A1 Le(a-b+) p phenotype: absence of blood group structures based on the globoseries

Total neutral glycolipid fractions were isolated from kidney and ureter tissue obtained at autopsy of an individual of the rare blood group A1 Le(a-b+) p. The amount of glycolipids isolated were 3.7 and 2.5 mg g-1 dry tissue weight for the kidney and ureter tissue, which is in the range of reference blood group P kidneys. Part of the kidney glycolipid fraction was subfractionated by HPLC. Glycolipid compounds were structurally characterized by thin-layer chromatography (chemical detection and immunostaining with monoclonal antibodies), proton NMR spectroscopy and mass spectrometry. Globotriaosyl- and globotetraosyl-ceramides, which are the major compounds in kidneys of P individuals, were absent in the p kidney, and a comparatively increased amount of monoglycosyl- and lactosylceramides was found. A shift to longer fatty acyl chains in the ceramide part of lactosylceramides was noted. Elongated globoseries compounds with five to seven sugar residues, including the blood group A type 4 chain structure, were lacking. A slight increase in neolactotetraosyl- and blood group X pentaglycosyl-ceramides was noticed. The study confirms an enzymatic block in the conversion of lactosylceramide to elongated globoseries compounds in the kidney tissue similar to that of erythrocytes of p individuals.

Muscarinic binding sites of the pig intravesical ureter

1. Muscarinic receptors in the pig intravesical ureter were characterized by binding assays in which the muscarinic receptor antagonist, (-)-[3H]-quinuclidinyl benzylate ([3H]QNB) was used as radioligand. 2. The specific binding of [3H]-QNB (about 90% of the total binding, as defined with 10(-5) M unlabelled atropine) was dependent on protein concentration, saturable, and of high affinity (KD = 0.13 +/- 0.02 nM). 3. Displacement of [3H]-QNB specific binding by the M1-selective antagonist, pirenzepine, described a two-component curve, with a minor (17%) high affinity component (pKiH = 8.75), and a major (83%) low affinity one (pKiL = 6.34). The M3-preferential antagonists, hexa-hydro-sila-difenidol (HHSid) and p-fluoro-HHSiD (p-F-HHSiD) delineated also two sites, with pKiH of 8.91 and 8.57 and pKiL of 6.94 and 7.05, respectively. However, the M2-selective antagonists, 11-(2-(diethyl-amino)methyl-1-piperidinylacetyl)-5,11-dihydro-6H-p yrido-(2,3-b)- (1,4)-benzodiazepin-6-one (AF-DX 116, pKi = 6.72) and methoctramine (pKi = 8.34), as well as the M4-selective antagonists, tropicamide (pKi = 7.15) and himbacine (pKi = 8.65) fitted best to a single population of sites. Moreover, 4-diphenyl-acetoxy-N-methyl-piperidine methiodide (4-DAMP), a muscarinic antagonist that discriminates the M1 and M3 versus the M2 subtypes, also delineated one site (pKi = 8.36). 4. The antagonist profile clearly indicates the existence of an M2 population in the porcine intravesical ureter. In addition, the presence of a minor non-M2 population, which may be formed by a mixture of several muscarinic subtypes (i.e. M1, M3 and/or M4) can not be discounted. 5. The present work confirms the results obtained in previous functional studies where the stimulation of muscarinic receptors by carbachol evoked the contraction of the pig isolated intravesical ureter.

Patterns of splice variant CD44 expression by normal human urothelium in situ and in vitro and by bladder-carcinoma cell lines

CD44 core and splice variant exon expression was investigated in the stratified transitional epithelium of the urinary tract and in normal and malignant bladder epithelial cell lines in vitro. Antibodies against core CD44 epitopes and splice exon variants v3, v4/5, v5 and v6 showed an intense reaction in the basal and lower intermediate urothelial cell layers, which was consistently lost from the upper intermediate and superficial cell layers. Seven independent cell lines established from normal human urothelium expressed complex multiple-spliced CD44 mRNA transcripts when tested by RT-PCR and were positive with antibodies against CD44 core epitopes and splice variants v3, v4/5, v5 and v6. Of the 13 bladder-carcinoma cell lines, all were positive for CD44 core. The more differentiated cell lines had retained some splice-variant antibody reactivity and showed multiple but less complex CD44 mRNA transcript patterns, compared with normal cells. Anaplastic cell lines did not react with variant antibodies and did not contain multiple-spliced CD44 transcripts. These data suggest that loss of alternatively-spliced CD44 may reflect a selection pressure in the evolution of anaplastic bladder cancers.

Abnormal innervation and altered nerve growth factor messenger ribonucleic acid expression in ureteropelvic junction obstruction

The pathophysiology of ureteropelvic junction obstruction is unknown. Using specific antibodies, we studied specimens from 35 cases of ureteropelvic junction obstruction and 32 of normal ureteropelvic junction by immunohistochemistry using protein gene product 9.5 (a general neuronal marker), S100 (a supporting cell marker), synaptophysin (a neuromuscular junction marker) and nerve growth factor receptor. Nerve growth factor expression was examined at the messenger ribonucleic acid (mRNA) level using reverse transcription-polymerase chain reaction technique in 11 ureteropelvic junction obstruction specimens and 7 controls. The most striking finding was the marked reduction of protein gene product 9.5, synaptophysin and nerve growth factor receptor staining positive nerve fibers in the muscle layers of ureteropelvic junction obstruction compared to the normal ureteropelvic junction. Supporting nerve cell fibers (S100) were preserved in cases of ureteropelvic junction obstruction and normal ureteropelvic junction. A significantly less intense signal for nerve growth factor mRNA was found in the ureteropelvic junction obstruction specimens compared to normal ureteropelvic junction. These findings suggest that defective innervation may have an important role in the pathogenesis of ureteropelvic junction obstruction, and decreased nerve growth factor mRNA expression may be important in the etiology of ureteropelvic junction obstruction.

Clonal chromosome changes in non-neoplastic ureters

Cytogenetic analysis was performed on 23 samples from non-neoplastic ureters. Clonal chromosome abnormalities were found in eight. They were: loss of Y chromosome, as a single abnormality (five cases) or associated with trisomy 10 and 20 (one case) or with trisomy 2 (one case); and duplication of Y chromosome (one case). Different numerical and structural sporadic abnormalities were found in nine cases. Immunohistochemical analysis and direct observation using the inverted microscope showed that the cells were mainly of the fibroblastic type. FISH analysis with chromosome 7 alpha-satellite probes failed to detect the presence of trisomy 7 in three epithelial cases tested.

Effect of carbachol and norepinephrine on phosphatidyl inositol hydrolysis and cyclic AMP levels in guinea pig urinary tract

Muscarinic cholinergic and adrenergic agonist-induced changes in [3H]-phosphatidyl inositol (PI) hydrolysis and cyclic AMP (cAMP) levels were measured in guinea pig ureter, urethra and bladder dome. In the ureter, carbachol, norepinephrine and phenylephrine rapidly increased PI hydrolysis and basal cAMP levels, but did not decrease forskolin-stimulated cAMP levels. In the bladder dome, norepinephrine and phenylephrine produced a rapid but transitory increase in PI hydrolysis, but did not affect forskolin-stimulated cAMP levels. Carbachol produced a rapid and sustained increase in PI hydrolysis and also, at high concentrations, decreased forskolin-stimulated cAMP levels. In the urethra, norepinephrine and carbachol rapidly decreased forskolin-stimulated cAMP levels and later increased PI hydrolysis. Our data suggest that the predominant second messenger system in the ureter, dome, or urethra is more dependent on the tissue than on the agonist. These tissue-specific, agonist-induced rapid changes in second messenger levels may help coordinate the contraction-relaxation phenomena necessary for urinary tract function.

Autoradiographic localization of NK1 and NK3 tachykinin receptors in rat kidney

The distribution of neurokinin receptors in rat kidney, renal artery, renal vein, and proximal ureter was evaluated by autoradiography after in vitro labeling of NK1 sites with [125I]Bolton-Hunter substance P (BHSP) or NK3 sites with [125I][MePhe7]neurokinin B ([MePhe7]NKB). Film autoradiography using [125I][MePhe7]NKB revealed specific binding sites associated with the renal vein and its large branches, the renal pelvis, the inner strip of outer renal medulla, and the proximal ureter. High-resolution autoradiograms demonstrated that these sites were localized to the smooth muscle layer in the veins, pelvis, and ureter. Neither the renal arterial system nor the renal cortex contained specific [125I][MePhe7]NKB binding sites although a high level of nonspecific binding was associated with the renal artery. Specific binding of [125I]BHSP was associated with the renal artery and renal pelvis but not the renal veins. Arterial NK1 receptors appeared to be localized to the adventitia. The results indicate that at least two types of tachykinin receptor are present in the rat kidney. The distinct localization observed for most of the NK1 and NK3 receptors suggests that they have different functions.

Dopamine D1 and D2 receptors in the human ureter and urinary bladder: a radioligand binding and autoradiographic study

OBJECTIVE

To analyse the pharmacological profile and the anatomical localization of the dopamine D1 and D2 receptors in sections of the pelvic part of the ureter and of the fundus of the urinary bladder.

PATIENTS, MATERIALS AND METHODS

Samples of the pelvic part of the ureter and of the fundus of the urinary bladder were taken in men (age range 61 +/- 4 years) who were undergoing lower urinary tract surgery. Biochemical characterization and autoradiographical techniques were used on frozen sections of the ureter or the urinary bladder. [3H]-SCH 23390 was used as a ligand of dopamine D1 receptors and [3H]-spiroperidol as a ligand of dopamine D2 receptors.

RESULTS

[3H]-SCH 23390 and [3H]-spiroperidol were bound by specific sections of the ureter and of the urinary bladder. The pharmacological profile of the binding was consistent with the labelling of D1 and D2 receptors respectively. Light microscope analysis of the localization of D1 and D2 receptors revealed the accumulation of the two radioligands in the tunica muscularis of the ureter or of the urinary bladder.

CONCLUSION

A possible role of the dopaminergic system in the control of urine flow and of some dysfunctions of the lower urinary tract is suggested.

An immunohistochemical study of the innervation of the ureterovesical junction in infancy and childhood

OBJECTIVE

To use histological and immunohistochemical methods to study the structure and innervation of the human ureterovesical junction (UVJ).

MATERIALS AND METHODS

A series of 24 post-natal specimens taken from patients ranging in age from 1 month to 6 years were examined. Routine histological slides were stained with Masson's trichrome. In addition, an indirect immunohistochemical method was used to study the occurrence and distribution of nerves immunoreactive for the neuropeptides vasoactive intestinal polypeptide (VIP), neuropeptide Y (NPY), substance P (SP) and calcitonin gene-related peptide (CGRP). Immunoreactivity to tyrosine hydroxylase (TH), dopamine-B-hydroxylase (DBH) and to protein gene product (PGP) 9.5, a general nerve marker, were also studied.

RESULTS

The UVJ comprised a ureteric muscle component (the intramural ureter) and a detrusor component (the immediately adjacent region of the urinary bladder). In the majority of specimens a third or intermediate layer was also present. This additional component consisted of tightly-packed smooth muscle cells which formed an incomplete layer that partially surrounded the juxta-vesical and intramural parts of the ureter. Numerous PGP-, VIP-, NPY, DBH- and TH- like immunoreactive (-LIR) nerves were associated with the smooth muscle bundles which comprised the intramural ureter. Such nerves ran in the connective tissue separating ureteric smooth muscle bundles and rarely coursed amongst individual smooth muscle cell comprising each bundle. SP- and CGRP- containing nerves were rarely observed in association with the intramural ureter and none were detected in the ureteric submucosa. The intermediate muscle layer was richly innervated by PGP-, TH-, DBH- and NPY- containing nerves which ran amongst the smooth muscle cells comprising this layer. VIP-, SP- and CGRP-LIR nerves were not observed within the intermediate layer. The detrusor component of the UVJ was innervated by PGP-, NPY- and VIP-LIR nerves which frequently extended between the smooth muscle cells forming the detrusor muscle bundles. TH-, DBH-, SP- and CGRP-LIR nerve fibres were rarely encountered.

CONCLUSION

These findings indicate that noradrenergic nerves play a major role in the control of the ureteric component of the UVJ. In addition, the present results form baseline morphological data with which to compare the results of future studies on the structure of the UVJ in cases of vesicoureteric reflux.

Histological and histochemical study of the vesicoureteric junction in infancy and childhood

The morphology of the vesicoureteric junction was compared using 19 post mortem specimens obtained from male and female Afro-American and Caucasian children with an age range of 1 to 72 months (mean 4). All specimens were serially sectioned and the tissues processed using standard histological and histochemical techniques (acetylcholinesterase ¿AChE¿ and pseudocholinesterase ¿PChE¿). The results failed to reveal any differences in the structure of the vesicoureteric junction with respect to age, sex and ethnic origins. The vesicoureteric junction comprised 3 histologically and histochemically distinct smooth muscle components. Ureteric muscle formed a complete inner layer rich in PChE which continued beyond the ureteric orifices to merge distally with the superficial trigone. An intermediate layer of muscle was also demonstrated whose constituent muscle cells possessed specific histological features and which was rich in both AChE and PChE, which is distinct from that derived from the ureter and detrusor. The presence of detrusor muscle on the outer aspect of the juxtavesical segment of ureter rich in AChE was also confirmed. While this study, using histochemical studies in infants and children, did not reveal any differences in the structure of the vesicoureteric junction with respect to age, sex or ethnic origin, an intermediate layer of muscle was identified with histochemical characteristics more like that of the male genital tract than that derived from the ureter or detrusor muscle.

Study of tyrosine hydroxylase and neuropeptidergic innervation of the human obstructed pelveoureteral junction in four different patients

Tyrosine hydroxylase and neuropeptidergic innervations of the obstructed pelveoureteral junctions of four different patients were investigated by immunohistochemical methods. A dense innervation of tyrosine hydroxylase- and neuropeptide Y-nerves was found especially in the pelveoureteral junction, which was congenitally obstructed, compared to others found later (13- and 23-year old females). Also quite numerous vasoactive intestinal polypeptide-nerves were seen as well as some calcitonin gene-related peptide-, galanin- and substance P-nerves in the muscular layer of ureter. The innervation pattern of the obstructed pelveoureteral junction of the horseshoe kidney was found to be normal.

Collagen arrangements in ureter

The collagen fibres of rabbit and human ureter were exposed by digestion with trypsin and hyaluronidase. The fibre structure was examined using an SEM and examples of the inner and outer fibre structures are shown together with the effects of different types of mechanical strain. An interesting difference between the arrangements of the inner fibres of human and rabbit was seen where the human ureter had a cross-ply structure while in the rabbit it was helical.

Lewis blood group antigen expression by cultured normal ureteral epithelial cells

The importance of Lewis blood group antigens in recurrent urinary tract infections has led to a more detailed study of the expression of these antigens in an in vitro culture system. Expression of A, B, H, and Lewis blood group antigens by primary cultures of ureter epithelial cells was analyzed by flow cytometry. Cells maintained blood group determinants for up to 7 weeks in culture over three passages. In several specimens, the cells that exhibited expression of Lewis A (Le(a) and Lewis B (Le(b)) antigens increased dramatically over 2-3 passages in culture. Lewis Y (Le(y)) antigen expression was positive on all primary cultures tested. The effect of fetal bovine serum (FBS) on blood group antigen expression was evaluated. Increased concentrations of FBS in the growth media increased the expression of Le(a) and Le(b) antigens in certain specimens, but did not affect expression of the other blood group antigens. The effect of FBS on blood group antigen expression of cultured cells depended on the Lewis blood type of the individual donating the specimen. To evaluate the heterogeneity often seen in Le(a) and Le(b) antigen expression, dual staining of cells for Le(a) and Le(b) antigens was performed. The results of these studies show for the first time that Lewis blood group antigens are expressed by cultured normal ureteral epithelial cells and that the pattern of expression of Le(a) and Le(b) changes over time. Furthermore, an individual cell may simultaneously express more than one Lewis antigen on its surface.

Alpha-fetoprotein-producing adenocarcinoma of the ureter

We report a case of primary ureteral tumor producing alpha-fetoprotein (AFP). Computerized tomography, ultrasonography and endoscopy of the bile duct revealed no obvious tumor in the liver, gallbladder, bile duct, pancreas or ovary. Total nephroureterectomy was performed, and histopathological examination revealed adenocarcinoma of the ureter lined with transitional cell carcinoma in its base. The tumor was stained with immunohistological AFP stain, and the high serum AFP level normalized after resection of the tumor.

[Detection of polyamines by a new enzymatic differential assay. (8) Studies on tissue polyamine concentrations in patients with genitourinary malignant diseases]

Polyamine concentrations of human cancerous and non-cancerous tissues from the kidney, ureter, bladder were measured by a new enzymatic method for isolation and determination of polyamines. In cancerous and non-cancerous tissue of the organs studied, the spermine level was highest followed by the spermidine and diamine levels. The concentrations of diamine, spermidine and spermine in cancerous tissues were significantly higher than those in non-cancerous tissues, but there was no significant difference in the spermidine/spermine ratio between the cancerous and non-cancerous tissues. These data suggest that polyamines are produced above the normal levels in pathological conditions such as renal cell carcinoma, ureteral cancer and bladder cancer.