Effects of theophylline and isoproterenol on the activity on the isolated guinea pig ureter.

To determine the role of the autonomic nervous system and of cyclic AMP in the control of ureteral peristalsis, isolated guinea pig ureters were placed in a 20-ml organ bath containing modified Krebs solution. Theophylline induced significant dose-dependent reduction in frequency and amplitude of contractions of the ureter hypertonified with barium chloride. No change in frequency or amplitude of contractions was observed with isoproterenol. Besides, our data explain why beta-agonist drugs are of very little value in the treatment of renal colic due to spasms of the pelviureteral tract.