Recovery of distal nephron enzyme-activity after release of unilateral ureteral, obstruction

VALLES, PATRICIA; MERLO, VERÓNICA; WALTER BERON; MANUCHA, WALTER

JOURNAL OF UROLOGY

ELSEVIER SCIENCE INC

Lugar: Amsterdam; Año: 1999 vol. 161 p. 641 - 648

0022-5347

PURPOSE: Unilateral ureteral obstruction (UUO) for 24 hours results in a severe compromise of distal tubular function. The acidification defect is believed to be localized in the collecting duct. To characterize distal tubular function recovery one month after junction release, clearance studies in whole animals and enzyme studies in microdissected segments were performed in an experimental model of unilateral ureteral obstruction. MATERIALS AND METHODS: Following release of ureteral obstruction of 24 hours duration, a significant decrease of whole kidney glomerular filtration rate was observed in the postobstructed kidney (POK) with a marked increase in urinary pH, fractional excretion of bicarbonate (FEHCO3-) and decrease in urinary osmolality. By orthograde stop flow experiment, bicarbonate excretion rate (Fr:Ff HCO3-/Fr:Ff Inutest) increased in the first and second urine fractions of 120 microl. corresponding to the collecting segment in the POK, one day after release. Decrease in U-P pCO2 (p