Immunohistochemical and electron microscopic examination of Cajal cells in ureteropelvic junction obstruction

Abstract

E311Cite as: Can Urol Assoc J 2013;7(5-6):e311-6. http://dx.doi.org/10.5489/cuaj.11293 Published online May 13, 2013 (early released September 10, 2012). AbstractObjective: We examine the ultrastructural configurations of Cajal cells by electron microscopy, as well as the quantitative changes occurring in Cajal cells by light microscopy. Methods: In total, 35 patients with ureteropelvic junction (UPJ) obstruction and 7 patients without obstruction were compared immunohistochemically with c-kit (CD117) to quantify the number of cells. On electron microscopic examination, 7 patients with UPJ obstruction and 3 patients without obstruction were compared to evaluate the changes which occurred in the ultrastructural configuration of the Cajal cells. Results: On light microscopic examination, it was determined that the Cajal cells, which demonstrate c-kit (CD117) immunoreactive character, were located near the circular muscle layer and parallel to the muscle cells. The number of Cajal cells in the control group was significantly increased compared to the number of cells in patients with UPJ obstruction (p < 0.001). On electron microscopic examination, the number of interstitial cells was also higher in the control group. A decrease in the number of the caveolae in these cells was seen in the group with UPJ obstruction compared to the control group. Conclusion: In UPJ obstruction, a decrease in the number of Cajal cells, as well as the changes in the morphologic structure of the Cajal cells, indicates that these cells have a role in the pacemaker system and are associated with ureteral peristalsis.

Telocyte and Cajal cell distribution in renal pelvis, ureteropelvic junction (UPJ), and proximal ureter in normal upper urinary tract and UPJ obstruction: reappraisal of the aetiology of UPJ obstruction

“…Cajal cells which are c-kit positive were demonstrated in this study in the muscular layer of normal UUT and in UPJO. Identification and characterization of these cells and their differentiation from other interstitial cells were in accordance with descriptions by previous studies on the upper urinary tract using IHC and TEM [3,4,5,6,7,8,9,11,20]. In our study, we showed that, in the normal UUT, Cajal cells were densely present in the proximal ureter, excessively in the renal pelvis, and moderately dense in the UPJ segment.…”

“…Our results differ from previous studies [3,4 ,7,15,21] where only the UPJ segment was examined and changes in proximal ureter and renal pelvis were not considered. Elken et al [4] searching for Cajal cells in the UPJ segment in UPJO in pediatric patients, found out that the Cajal cells were either rare or absent. Our study confirmed their presence in the UPJ segment in UPJO, although not in the same density as in the normal UPJ segment.…”

“…They are distinct from smooth muscle cells, fibroblasts, and monocytes, the surface membrane has abundant invaginations and prominent endoplasmic reticulum, they are characterized by being uninucleate with thin cytoplasm and numerous mitochondria [4,5,7,8,19,11,20]. Low density or altered function of Cajal cells were attributes to the etiology of UPJ obstruction [3,4,7,15,21]. Elken et al [4] studied UPJ specimens from patients with UPJ obstruction and normal control, examining them with TEM, light microscopy, and immunohistochemical stain.…”

“…Low density or altered function of Cajal cells were attributes to the etiology of UPJ obstruction [3,4,7,15,21]. Elken et al [4] studied UPJ specimens from patients with UPJ obstruction and normal control, examining them with TEM, light microscopy, and immunohistochemical stain. They found out that the c-kit positive-stained cells were located near the circular muscle layer and were encountered more frequently in the control group.…”

Variations in the Density and Distribution of Cajal Like Cells Associated With the Pathogenesis of Ureteropelvic Junction Obstruction: A Systematic Review and Meta-Analysis

“…Ureteric innervation is to the muscular and subepithelial layers (51) where the nerve endings reside, therefore the deficiency in CLCs in serosal layer could be due to the lack of sensory nerve endings in the serosa. Majority of the studies suggest that the overall CLC density at UPJ is reduced in individuals with UPJO compared to controls (33,38,40,42,45), which is consistent with the results of our quantitative synthesis. A constellation of gastrointestinal motility diseases including achalasia cardia (52) and Hirschsprung's disease (53) are associated with depletion of Cajal cells, while reduction of Cajal cell density in small intestinal segments of inflammation or obstruction significantly improves when treating the pathology causing inflammation or removal of obstruction (54,55).…”