title: Relaxant effect of thiphenamil HCl on upper urinary tract frequency of contraction of healthy asymptomatic volunteers.
abstract: The pharmacologic effect of thiphenamil HCl on the upper urinary tract as a relaxant of renal pelvic contractions was studied. A total of 17 subjects with no known upper urinary tract abnormalities were scanned. A Diasonics ultrasound scanner at 3.5 MHz was used to visualize the kidney and renal pelvis with the subject in the supine position. Control recordings of renal pelvic and calyceal contractility were made on videotape for approximately 30 min. The subject was then given a single dose of 400 mg thiphenamil HCl and visualization of contractility continued for approximately 60-90 min. Criteria for the evaluation of the data were the mean frequency of pelvic contraction cross-section of the pelvis, and velocity and direction contraction. Ultrasonic images were filtered by a video filtering process and averaged using the digital conversion and summation in real time. The results show that under control conditions renal pelvic contractions are at a frequency of 2 +/- 1.8 min-1. Contractions are initiated with the intrarenal pelvis and continue towards the ureter at a rate of 1.3 +/- 0.8 cm/s. Following thiphenamil HCl, there is a significant reduction in pelvic contraction frequency, 0.6 +/- 0.6 min-1, and the opposing walls of the renal pelvis do not completely close in the formation of a bolus. The results obtained from this study demonstrate that thiphenamil suppresses upper urinary tract contractility. As a consequence of this observation, it is postulated that this agent may be of use in the acute relaxation of the upper urinary tract for renal colic and stone management.
authors.affiliation: Division of Urology, Stanford University School of Medicine, Calif.
authors.forename: C E
authors.initials: CE
authors.lastname: Constantinou
mesh_terms: D004158:Diphenylacetic Acids / Q000494:pharmacology*; D005260:Female; D006801:Humans; D007682:Kidney Pelvis / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology; D009126:Muscle Relaxation / Q000187:drug effects*; D009130:Muscle, Smooth / Q000187:drug effects* / Q000502:physiology; D010276:Parasympatholytics / Q000494:pharmacology*; D013457:Sulfur Compounds; D014463:Ultrasonography; D014513:Ureter / Q000000981:diagnostic imaging / Q000187:drug effects* / Q000502:physiology
chemical_list: D004158:Diphenylacetic Acids; D010276:Parasympatholytics; D013457:Sulfur Compounds; C009488:thiphenamil