EXPERIMENTAL POLYHYDRAMNIOS AND HYDROPS FETALIS

实验性多汗症和胎儿水肿

• 批准号: 6272391
• 负责人: JOB J. FABER
• 金额: $ 16.91万
• 依托单位: OREGON HEALTH & SCIENCE UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 1998
• 资助国家: 美国
• 起止时间: 1998-06-01 至 1999-05-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6272391
• 关键词: angiotensins; antihypertensive agents; body water; cardiovascular disorder chemotherapy; edema; electrolytes; embryo /fetus; embryo /fetus disorder; hemodynamics; hormone regulation /control mechanism; nephrectomy; placenta disorders; placental transfer; pregnancy circulation; renin angiotensin system; sheep

The most consistent and vigorous fetal cardiovascular response occurs in the defense of fetal (rental) arterial blood pressure, as elicited, for instance, by supra-renal stenosis of the fetal aorta. Part of this response is the activation of the fetal renin angiotensin system. When angiotensin is chronically infused into normal fetuses, at very low dose rates, there is a slowly developing but very large increase in fetal arterial blood pressure. But there is also a great increase in placental water transfer into the fetus, as evidenced by polyhydramnios in intact fetuses and hydrops fetalis in nephrectomized fetuses. It is hypothesized, therefor, that the modulation of placental water transfer from the mother into the conceptus is part of the homeostatic mechanism that controls fetal arterial pressure and that polyhydramnios and hydrops are derailments of that homeostatic mechanism. Specific aims of the proposed experiments are, first, to unravel the physiological regulation mechanism that acts within the placenta to control water transfer and, second, to quantify the relevant hemodynamic and membrane parameters. Fetal sheep with indwelling catheters and electronic instrumentation will be used. Placental flows and pressures will be measured in the presence of partial venous obstruction with and without the concomitant administration of angiotensin. The long-term goal of our research program is to help clarify the pathophysiology of human polyhydramnios, a common disease of pregnancy, and of hydrops fetalis, an uncommon but usually fatal disease of the newborn.

最一致和最强烈的胎儿心血管反应发生在