Bogaert G A, Mevorach R A, Kogan B A
Department of Urology, University of California School of Medicine, San Francisco.
J Urol. 1994 Jul;152(1):220-5. doi: 10.1016/s0022-5347(17)32866-5.
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.
我们对胎羊进行了研究，以明确子宫内慢性部分膀胱出口梗阻的肾脏病理生理学。这些胎羊妊娠115至120天（足月为145天），接受了尿道结扎、脐尿管导管置入以及在左肾动脉周围放置超声流量传感器。通过在脐尿管和羊膜导管之间放置一个狭窄的连接器造成部分梗阻。在对照动物中，放置一个大的连接器以使膀胱能自由引流至羊膜腔。每天测量肾血流量，并在第5天和第10天收集尿液以评估肾功能。在对照动物中，未观察到任何参数有显著变化。在部分梗阻的胎羊中，肾血流量在5天后增加至基线的165%；从第5天到第10天，它有所下降，但在第10天时仍高于基线值（128%）。10天后尿量显著下降（67%）。肾小球滤过率在5天后略有增加（127%），但在10天后下降（56%）。滤过分数在5天（70%）和10天后（33%）稳步下降。钠排泄分数和总钠排泄量没有变化。在胎羊中，对部分膀胱出口梗阻的反应是，在10天的时间里肾血流量增加、滤过分数降低且肾功能逐渐减弱。
