Effects of verapamil, prostaglandin F2 alpha, phenylephrine, and noradrenaline on upper urinary tract dynamics

The effects of verapamil (VRP), prostaglandin F2 alpha (PGF2 alpha), phenylephrine, and noradrenaline on upper urinary tract dynamics were studied in vivo, using a pig model involving 12 miniswine which were subjected to acute pharmacologic perfusion studies of the upper urinary tract.

Changes in renal pelvic pressure (Ppvs) and ureteral peristalsis frequency were recorded at 2 mL/min perfusion rate premedication, and then during perfusion with different concentrations of each drug tested in three experiments.

Ppvs showed no significant variations with VRP perfusion when compared with premedication readings, whereas ureteral peristalsis frequency was decreased significantly by 10(-3) mol/L of VRP. PGF2 alpha perfusion caused no statistically significant changes in Ppvs when compared with premedication values, but increased ureteral peristalsis frequency from 3 to 6.5/min at a concentration of 2 x 10(-1) mg (200 micrograms). Phenylephrine HCl and noradrenaline perfusion increased Ppvs from 8 +/- 1.1 to 11.9 +/- 1.6 cm water at a concentration of 100 micrograms. They augmented the frequency of ureteral peristalsis from about 2.5 +/- 1.2 to 4.1 +/- 1.3/min. No systemic effects were recorded since pulse, respiration, and left ureteral activity were unchanged during pharmacologic perfusion of the right side.

Pharmacologic manipulation of ureteral activity can be achieved via direct perfusion with no significant modulation of Ppvs or systemic impact. VRP-induced smooth muscle relaxation of the upper urinary tract may be useful in percutaneous surgery for stones.