The incidence of ecotpic peristaltic contractions.

The continuity of ureteral peristaltic conduction along the ureter of the dog is examined using two pairs of extracellular macroelectrodes. At urine flow rates below 3 ml/min, ureteral contractions initiated by the pacemaker are propagated without interruption along the entire length of the ureter, and at sustained diuretic levels greater than 3-5 ml/min, ectopic peristaltic and retrograde events may be initiated along the length of the ureter. Also, continued maintenance of diuresis results in decremental conduction along the upper third of the ureter with the ultimate possiblity of pacemaker failure.