Transport efficiency of ureteral peristalsis correlated to pacemaker activity of renal pelvis

The transport efficiency of ureteral peristalsis under the control of the pacemaker was examined during renal pelvic perfusion in dogs. Simultaneous recordings of the perfusion rate, renal pelvic pressure, ureteral electromyogram, and bolus volume were made during each period of perfusion at a constant rate. For a graphic representation of transport efficiency of each peristaltic contraction, changes in balance level between the perfusion rate and the bolus volume were registered by a presettable binary counter. A quantitative evaluation of transport efficiency was also made of each group of peristaltic contractions that was classified by its characteristic distribution of the interperistaltic internal. The pacemaker activity of the renal pelvis and its control of ureteral peristalsis were identified in this preparation. Most of the peristaltic contractions excreted the same volume of fluid that had entered the pelviureteral system during the preceding period of nonperistalsis within the range of studied perfusion rates. The transport efficiency defined as interperistaltic interval x perfusion rate/bolus volume showed a small variation around the value 1 for peristaltic contractions in each group.