Spontaneous rhythmic activity of the urinary system: the role of interstitial cells, the biological significance, pathophysiological aspects (literature review)

In this literature review we examine the current data on the physiological roles and mechanisms of spontaneous rhythmic contractile activity of the urinary system and prostate. The data shows that in the upper urinary tract the spontaneous rhythmic activity mainly provides transportation of urine, whereas in the lower urinary tract and prostate gland it is associated with regulation of the tonus of these organs. The pacemaking role of atypical smooth muscle cells (ASMC) capable of rhythmic fluctuations in membrane potential due to the cyclic release of calcium and interstitial Cajal like cells (ICC) also having auto rhythmicity in the generation of spontaneous contractions and their relationship to each other in various organs are discussed In upper urinary tract according to modern concepts the leading pacemaker role have ASMC, while ICC take part in amplification and spread of impulse on the surrounding typical smooth muscle cells and modulation of contractile activity under the influence of autonomic nervous system. With regard to the bladder the question of leadership between two systems has not been resolved definitely yet and still widely discussed, as in the case of prostate gland, while for urethra there is more data for the leading role of ICC The significance of violation of rhythmic contractile activity mechanism and the role of ICC in the development of upper and lower urinary tract pathologies, in particularly, violation of urine transportation through ureters in patients with overactive bladder and incontinence are discussed