Affiliation:
1. Department of Physiology, Tulane University School of Medicine, New Orleans, La 70112.
Abstract
Renal tissue angiotensin I (Ang I) and II (Ang II) content and angiotensin converting enzyme activity were assessed in both kidneys during initial (7 days) and maintenance (25 days) phases of two-kidney, one clip hypertension in rats. At 7 and 25 days, systolic arterial pressure was 146 +/- 2 and 170 +/- 7 mm Hg, respectively. After 7 days, Ang I content of clipped kidneys was 64% and 70% higher (p < 0.001) than in nonclipped and sham-operated kidneys, respectively, when compared with levels in kidneys from sham-operated rats. In kidneys harvested 25 days after clipping one renal artery, Ang I and Ang II contents in clipped kidneys were increased 102% and 24% (p < 0.01), respectively. Ang II content was also 32% higher in nonclipped kidneys. Angiotensin converting enzyme activity in nonclipped kidneys was greater (p < 0.05) than that in either clipped (46% higher) or sham-operated kidneys (57% higher). Plasma Ang I and Ang II levels were elevated at 7 days but were not different at 25 days in clipped rats. These results demonstrate a dissociation between intrarenal and circulating levels of Ang I and Ang II and suggest that qualitatively different mechanisms may be responsible for the elevated intrarenal Ang II levels during the initial and maintenance phases of renal hypertension.
Publisher
Ovid Technologies (Wolters Kluwer Health)
Reference21 articles.
1. l. Navar LG Huang WC Mitchell KD Jackson CA Ploth DW: Renal mechanisms of hypertension in Pholpramol C Sudsuang R (eds): Proceedings of the First Congress of the Asian and Oceanian Physiological Societies. Bangkok Thailand The Physiological Society 1987 pp 253-261
2. Angiotensin-dependent renal mechanisms in twokidney, one-clip renal vascular hypertension. Am;Ploth DW;Physiol,1983
3. Angiotensin II: Evidence for its role as an intrarenal hormone;Mendelsohn FAO;Kidney Int,1982
4. Impaired renal blood flow and cortical pressure autoregulation in contralateral kidneys of Goldblatt hypertensive rats.
5. Kramer P Ochwadt B: Sodium excretion in Goldblatt hypertension: Long term separate kidney function studies in rats by means of a new technique. Pflugers Arch 1972-32:332-345