Pacemakers in the upper urinary tract

Neurourol Urodyn. 2013 Apr;32(4):349-53. doi: 10.1002/nau.22310. Epub 2012 Sep 21.

Abstract

Background: Pacemakers in upper urinary tract (UUT) are still under study.

Aim: We reviewed the role of some cells that seem to be involved in the propulsion of urinary bolus from UUT to the bladder.

Materials & methods: We focuses on evaluating studies on the mechanisms by which the UUT propels urine to the bladder via pacemaker cells.

Results: Electric active pacemaker cells generate pyeloureteric autorhythmicity driving adjacent smooth muscle cells (SMCs); it emphasizes the role of the interstitial cells of Cajal-like cells (ICC-LCs) localized in the UUT. Interstitial cells of Cajal (ICCs) are now thought to cooperate in conducting and amplifying pacemaker activity in the UUT. These cells produce electrical slow-wave potentials and determine the propagation of peristaltic activity. Identification of ICC-LCs is facilitated by use of c-kit antibodies. Contraction waves arising from the UUT and the propagation of these waves may require the direct involvement of ICC-LCs, as c-kit immunoreactivity appears developmentally at the same time as coordinated unidirectional peristaltic contraction. ICC-LCs observed in the UUT have morphological features similar to those of c-kitpositive ICCs in the gastrointestinal tract. In addition to gastrointestinal motility, ICCs may also play a significant role in the propagation, coordination, and modulation of ureteropelvic peristalsis.

Discussion: Alterations in ICC-LCs are closely associated with a variety of motility disorders and many congenital urological diseases of the UUT such as primary obstructive megaureter, congenital ureteropelvic junction obstruction, and vesicoureteral reflux.

Conclusion: These observations open the way for further investigations of this cell type.

Publication types

  • Review

MeSH terms

  • Biological Clocks / physiology*
  • Electrophysiological Phenomena / physiology
  • Female
  • Humans
  • Male
  • Muscle Fibers, Skeletal / physiology
  • Muscle, Smooth / physiology
  • Ureter / abnormalities
  • Ureteral Obstruction / diagnosis
  • Ureteral Obstruction / physiopathology
  • Urinary Bladder / innervation
  • Urinary Bladder / physiology
  • Urinary Tract Physiological Phenomena*
  • Urologic Diseases / diagnosis
  • Urologic Diseases / physiopathology*
  • Vesico-Ureteral Reflux / diagnosis
  • Vesico-Ureteral Reflux / physiopathology