[A contractile function of various megaureter forms in infants and its pharmacological regulation].

A total of 43 infants under 3 years of age with organic, functional and reflux obstructive megaureter were studied. The function of the upper urinary tract was examined with dynamic pyeloureterosonography with diuretic load. Contractility of isolated fragments of megaureters and possibility of its pharmacological regulation were studied in patients after surgery in vitro. Different urodynamic variants of the response of refluxing and obstructive megaureters and those with functional obstruction on stimulation of diuresis were established at dynamic pyeloureterosonography with diuretic load. The differences concerned the strength and kind of the reaction, frequency, amplitude and performance of the megaureters (15-30-45 min). In vitro studies confirmed functional differences between the forms of megaureters. The data obtained show preservation of functional reserves of the wall of the refluxing megaureter in children, suppression contractions and reaction of the megaureters with organic obstruction in the ureterovesical anastomosis while functionally obstructive megaureters are able to contract slowly and have reactivity according to the state of the smooth muscle wall. Pharmacological impact on ureteral function by metabolic drugs (picamilone) is determined. A direct action of lasix on the smooth muscle (weakening of high toxic reaction) is proved.