Effect of Calyceal Resection on Pelviureteral Peristalsis in Isolated Pig Kidney

Abstract

Pelviureteral peristalsis in the isolated pig kidney with calyceal resection was studied by electromyography. Ureteral peristalsis normally remained under control of calyceal pacemakers while at least one of the upper, middle and lower major calyces of the isolated pig kidney was intact. After resection of all these calyces, uncontrolled spontaneous contractions began to arise from the renal pelvis, pelviureteral junction (PUJ) and stump of the ureter. In such kidneys, the PUJ and cut end of the ureter showed discharge potentials with irregular intervals while the potential recorded from the center of the pelvis had virtually constant intervals of discharge. The spontaneous contractions arising in the pelvis were rarely propagated to the PUJ and ureter, and there was irregular antiperistalsis of the ureter generating at the cut end and also irregular ureteral normoperistalsis originating at the PUJ and propagating to the ureter. With increased intrapelvic fluid infusion, the discharge interval of the renal pelvis shortened whereas that of the PUJ and ureter was prolonged. These facts suggest the importance of the calyceal pacemaker both as an origin of ureteral peristalsis and as a supervisor for maintaining normal ureteral peristalsis.