Von Thun A M, Vari R C, el-Dahr S S, Navar L G
Department of Physiology, Tulane University School of Medicine, New Orleans, Louisiana 70112.
Am J Physiol. 1994 Jan;266(1 Pt 2):F120-8. doi: 10.1152/ajprenal.1994.266.1.F120.
The objective of this study was to investigate the singular role of elevated angiotensin II (ANG II) levels in the development of two-kidney, one-clip (2K1C) Goldblatt hypertension in the rat and specifically in the altered intrarenal ANG II levels that occur in the nonclipped kidney. As a substitute for the clipped kidney, chronic delivery of ANG II (40 ng/min) via an osmotic minipump implanted subcutaneously was used to mimic plasma ANG II levels observed in 2K1C rats during the developmental phase of hypertension. Arterial pressure increased gradually over a period of 14 days, and a pressure profile similar in magnitude and temporal pattern to that of the 2K1C rats was observed. Systemic ANG II was elevated to similar levels in the 2K1C (60 +/- 13 fmol/ml) and ANG II-infused rats (72 +/- 15 fmol/ml) compared with intact two-kidney control animals (31 +/- 6 fmol/ml; P < 0.05) or uninephrectomized rats (13 +/- 1 fmol/ml; P < 0.05). Although renin content was markedly suppressed (80%), intrarenal ANG II content of the contralateral kidneys of the 2K1C groups (86 +/- 12 fmol/g) and the ANG II-infused group (150 +/- 17 fmol/g) was greater than that of the two-kidney control (53 +/- 7 fmol/g; P < 0.05) and uninephrectomized control animals (42 +/- 5 fmol/g; P < 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
本研究的目的是探讨血管紧张素II（ANG II）水平升高在大鼠二肾一夹（2K1C）型Goldblatt高血压发生过程中的独特作用，特别是在未夹闭肾脏中发生的肾内ANG II水平改变方面的作用。作为夹闭肾脏的替代方法，通过皮下植入的渗透微型泵持续输注ANG II（40 ng/分钟），以模拟2K1C大鼠在高血压发展阶段观察到的血浆ANG II水平。动脉血压在14天内逐渐升高，观察到其压力曲线在幅度和时间模式上与2K1C大鼠相似。与完整的双肾对照动物（31±6 fmol/ml；P<0.05）或单侧肾切除大鼠（13±1 fmol/ml；P<0.05）相比，2K1C组（60±13 fmol/ml）和ANG II输注组（72±15 fmol/ml）的全身ANG II升高到相似水平。尽管肾素含量明显受到抑制（80%），但2K1C组对侧肾脏（86±12 fmol/g）和ANG II输注组（150±17 fmol/g）的肾内ANG II含量高于双肾对照（53±7 fmol/g；P<0.05）和单侧肾切除对照动物（42±5 fmol/g；P<0.05）。（摘要截断于250字）
