title: Renal hemodynamic and functional effects of 10 days' partial urinary obstruction in the fetal lamb.
abstract: We studied fetal lambs to define the renal pathophysiology of chronic in utero partial bladder outlet obstruction. These fetal lambs, 115 to 120 days gestation (term = 145 days), underwent urethral ligation, placement of a urachal catheter and positioning of an ultrasonic flow transducer around the left renal artery. Partial obstruction was created by placing a narrow connector between the urachal and an amniotic catheter. In control animals a large connector was placed to allow free drainage of the bladder into the amniotic cavity. Renal blood flow was measured daily, and urine was collected at days 5 and 10 to evaluate renal function. In control animals, no significant changes in any parameters were observed. In the partially obstructed fetal lambs, renal blood flow increased to 165% of baseline after 5 days; from 5 to 10 days, it decreased, but remained above baseline values through 10 days (128%). Urine production dropped significantly after 10 days (67%). Glomerular filtration rate increased slightly after 5 days (127%), but decreased after 10 (56%). Filtration fraction steadily decreased after 5 (70%) and 10 days (33%). Fractional and total sodium excretion did not change. Renal blood flow increases, filtration fraction decreases and renal function trends progressively diminish in response to partial bladder outlet obstruction over a period of 10 days in the fetal lamb.
authors.affiliation: Department of Urology, University of California School of Medicine, San Francisco.
authors.forename: G A
authors.initials: GA
authors.lastname: Bogaert
authors.forename: R A
authors.initials: RA
authors.lastname: Mevorach
authors.forename: B A
authors.initials: BA
authors.lastname: Kogan
mesh_terms: D000818:Animals; D005260:Female; D005315:Fetal Diseases / Q000503:physiopathology*; D005919:Glomerular Filtration Rate / Q000502:physiology; D007668:Kidney / Q000196:embryology / Q000503:physiopathology*; D011247:Pregnancy; D012079:Renal Circulation / Q000502:physiology*; D012756:Sheep; D013997:Time Factors; D001748:Urinary Bladder Neck Obstruction / Q000196:embryology / Q000503:physiopathology*; D014556:Urine