Davis G, Johns E J
Department of Physiology, Medical School, Birmingham, UK.
J Med Eng Technol. 1990 Sep-Oct;14(5):197-200. doi: 10.3109/03091909009009961.
A comparison was made of the vascular actions of two hormones having a renal site of action, angiotensin II and vasopressin, using laser Doppler flowmetry to measure perfusion of the cortical and papillary regions of the kidney. Angiotensin II infusion caused dose-related increases in blood pressure and reductions in cortical perfusion, the latter responses being potentiated in the presence of the converting enzyme inhibitor, cilazapril. However, angiotensin II had no effect on papillary perfusion either before or following cilazapril. The reasons for this differing vasoconstrictor ability of angiotensin II at the cortex and papilla are unclear, but it could be due to medullary generation of prostaglandin or bradykinin. Administration of equipressor doses of vasopressin caused graded reductions in both cortical and papillary perfusions, and subsequent cilazapril significantly enhanced the papillary responses. This study demonstrates that the regulation of blood flow through the different regions of the kidney can be differentially regulated by the peptide hormones angiotensin II and vasopressin.
利用激光多普勒血流仪测量肾脏皮质和乳头区域的灌注，对作用于肾脏的两种激素——血管紧张素II和血管加压素的血管作用进行了比较。输注血管紧张素II导致血压呈剂量依赖性升高，皮质灌注减少，在使用转换酶抑制剂西拉普利的情况下，后一种反应会增强。然而，无论在使用西拉普利之前还是之后，血管紧张素II对乳头灌注均无影响。血管紧张素II在皮质和乳头处的血管收缩能力不同，其原因尚不清楚，但可能是由于髓质中前列腺素或缓激肽的生成。给予等升压剂量的血管加压素会导致皮质和乳头灌注均逐渐减少，随后使用西拉普利可显著增强乳头的反应。这项研究表明，血管紧张素II和血管加压素这两种肽类激素对流经肾脏不同区域的血流调节存在差异。
