First Prize: Pharmacologic Manipulation of the Porcine Ureter: Acute Impact of Topical Drugs on Ureteral Diameter and Peristaltic Activity

Abstract

In the porcine model, intraluminal application of pharmacologic agents produced independent effects on ureteral dilation and peristalsis. Theophylline inhibited ureteral peristalsis, and verapamil produced acute proximal-ureteral dilation. The ability to alter ureteral diameter or peristaltic activity acutely may facilitate ureteroscopy.

Verapamil Inhibits the Pelvic Pressure Increase Corresponding to Flow Perfusion in the Porcine Percutaneous Renal Puncture Model

“…In the experimental group with a varied perfusion rate, we observed that the pressure-flow relationship was significantly inhibited at concentrations of 1, 10 and 100 µg/ml verapamil compared with that of the control group. It is suggested that verapamil effectively cause dose-dependent relaxation of renal pelvic smooth muscle, which is in accordance with the findings noted by Selmy et al [9 ]and Ames et al [18]. …”

“…Ureteral access sheath also can provide protection against elevated renal pressures during routine ureteroscopic stone surgery [23]. In addition, some documents reported that some β-receptor agonist can cause relaxation of the upper urinary tract and reduce the pelvic pressure, such as β2-agonists and β3-agonists [6,9,11,12,13,14,15,18,19,24,25]. …”

“…Various pharmacological agents have shown great potential for lowering pelvic pressure, such as isoproterenol, terbutaline, norepinephrine, prostaglandin synthetase inhibitors and adrenaline [6,8,9,10,11,12,13,14,15]. In addition, a great deal of evidence has demonstrated that calcium channel blockers (CCBs) are capable of relaxing the smooth muscle of the ureter and pelvis as well as relieving ureteral colic [16,17,18,19]. Verapamil, which is typical of CCBs, has been proven to possess the ability of inhibiting ureteral peristalsis and dilation of proximal-ureter [9,18].…”

“…In addition, a great deal of evidence has demonstrated that calcium channel blockers (CCBs) are capable of relaxing the smooth muscle of the ureter and pelvis as well as relieving ureteral colic [16,17,18,19]. Verapamil, which is typical of CCBs, has been proven to possess the ability of inhibiting ureteral peristalsis and dilation of proximal-ureter [9,18]. …”

Irrigation with isoproterenol diminishes increases in pelvic pressure without side-effects during ureterorenoscopy: A randomized controlled study in a porcine model

“…In clinically randomized studies [20,21], both a 1 -adrenoceptor blockers and nifidepine, administered orally, effectively reduced the expulsion time and the number of pain episodes in patients suffering from distal ureteral stones. An interesting approach to the evaluation of ureteral muscle tone has recently been described by Ames et al [22], who found that intraluminally administered verapamil significantly increases proximal ureteral diameter in pigs. The combination of a b-adrenergic agonist with either an a1-adrenergic antagonist or a calcium-channel blocker may therefore elicit an even better pressure-reducing effect.…”