THE INITIATION AND PROPAGATION OF THE RENAL PELVIC PERISTALSIS IN PIG KIDNEY WITH MULTICALYCEAL SYSTEM

Abstract

The initiation and propagation of the pelvi-ureteric peristalsis were studied through the direct observation of peristalsis, both microscopically and electrophysiologically. A microscopic ripple-like contraction of a constant frequency was generated spontaneously at the border between the upper, middle, and lower major calyces. At the same time electromyograms were recorded in the same region with constant discharge interval. Propagated waves were originated toward the ureter at different times from three major calyces, without infusion or with intrapelvic infusion. Without infusion, most pacemaker contractions usually disappeared within the calyces or pelvis, but when infusion was started, pacemaker contractions propagated toward the pelvis and ureter. Furthermore, when the solution was infused into only one calyx, the pacemaker contraction generating at the infused calyx always propagated toward the pelvis and ureter. I could not find a certain law as to which pacemaker peristalsis controls the contraction of the pelvis and ureter. But, amount of solution infused into the calyx, that is, urinary excretion into the calyx in vivo, was thought to be one of the important factors for propagation.