METAPLASTIC AND MITOTIC-ACTIVITY OF THE ISCHEMIC (ENDOCRINE) KIDNEY IN EXPERIMENTAL RENAL-HYPERTENSION

  • 1 January 1979
    • journal article
    • research article
    • Vol. 96  (2) , 545-565
Abstract
Partial ligation of the aorta between the renal arteries in the rat induces malignant hypertension, metaplasia of smooth-muscle cells of arterioles and arteries into juxtaglomerular cells and a complex series of events in tubular cells at all levels of the ischemic kidney. The tubular cells of the outer cortex, particularly the proximal convoluted cells, show a very rapid and progressive simple atrophy. Necrosis of individual cells is followed by mitotic activity in atrophic tubular cells of the inner cortex, medulla and papilla. Polyploidy and hyperplasia occur in the inner cortex. Hypertrophy of the protein-synthesizing apparatus and an increase in protein, DNA and RNA, followed by a decrease in the protein content, are seen in the tubular cells of the inner cortex. In the medulla and papilla, necrosis of individual cells proceeds side by side with waves of mitotic activity. These events take place, albeit to a lesser degree, even in cases of very mild renal ischemia. While they may be unrelated to hypertension, these changes are probably involved in the increase in hydrolytic enzyme activity characteristic of the ischemic renal cortex.