RENAL MEDULLARY FUNCTION AND ARTERIAL PRESSURE CONTROL

拟议中的研究将确定肾髓质是否在 在确定动脉血长期水平中的重要作用 压力。我们将慢性减少乳头血流量，看看是否 这会导致高血压和慢性乳头状血流量升高 如果这会导致低血压。有两种新技术是必要的，它们是 用于这些研究。一、植入性髓间质导管 靶向将物质输送到肾髓质，敏锐和 长期如此。另一种是急性和长期植入的光纤 在肾皮质、外髓和内髓测量变化 在局部血流中使用激光多普勒血流计。这些技术 已经被设计成在清醒的大鼠身上执行，在这个时候 可可靠使用3周以上。一系列 研究旨在确定肾髓质的急性影响 血管收缩剂和扩张剂的间质输注改变 乳头状血流会导致动脉慢性改变 压力。第三系列研究将确定慢性髓质 组织间输注增加乳头状血流量的化合物 SHR可重置血压-利钠关系并使其正常化 动脉压。积极的发现将支持这样的概念 髓功能的细微变化可能先于肾脏的整体变化 功能，并可能是一个重要的启动因素的病因。 高血压。

The proposed studies will determine if the renal medulla plays an important role in determining the long-term level of arterial blood pressure. We will chronically reduce papillary blood flow to see if this leads to hypertension and chronically elevate papillary flow to see if this leads to hypotension. Two new techniques were necessary and are used for these studies. One, implanted medullary interstitial catheters to target delivery of substances into the renal medulla, acutely and chronically. The other, acute and chronically implanted optical fibers in the renal cortex, outer and inner medulla for measurement of changes in regional blood flow using laser-Doppler flowmetry. These techniques have been designed to be performed in conscious rats and at this time can be used reliably for periods exceeding 3 weeks. One series of studies is designed to determine the acute effects of renal medullary interstitial infusions of vasoconstrictors and dilators which alter papillary blood flow will produce chronic alterations of arterial pressure. A third series of studies will determine if chronic medullary interstitial infusion of compounds that increase papillary blood flow in SHR can reset the pressure-natriuretic relationship and normalize arterial pressure. Positive findings would support the concept that subtle changes in medullary function may precede global changes in renal function and may be an important initiating element in the etiology of hypertension.