Abstract
During the study of an inbred strain of Wistar rats which spontaneously develop hypertension when they reach a weight of approximately 150 g, it was found that these animals also develop an erythrocytosis. A significant increase in red cell count was observed in spontaneously hypertensive (SH) rats (8-11 × 106 RBC/mm3) when compared with normotensive rats (6-7 × 106 RBC/mm3) of the same strain. This increase in red cell count paralleled the increase in body weight and the rise in blood pressure.
Since the plasma volume, as measured with labeled albumin was normal, there was an absolute increase in red cells. The hematocrit and hemoglobin content of the blood measured in SH rats were only slightly greater than those found in normotensive rats. However, the mean cell volume (MCV) of the red cells in the SH rats was 45-47 μ3 as compared with 51-53 μ3 in normotensive rats.
A fourfold increase in 24 hr 59Fe incorporation into the red cells was found in the SH rats when compared with normotensive controls. The bone marrow of the SH rats showed erythroid hyperplasia. When the SH rats were treated with α-methyldopa (Aldomet 200 mg/kg daily, i.p.) the red cell count fell in parallel with the drop in blood pressure. No change in red cell count or blood pressure was observed in normotensive rats treated in the same manner. The erythropoietin titer was high in SH rats, and was undetectable in normotensive rats. These observations suggest a direct relationship between the hypertension and the erythrocytosis mediated by erythropoietin; both are genetically controlled.
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Selected References
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- AOKI K. EXPERIMENTAL STUDIES ON THE RELATIONSHIP BETWEEN ENDOCRINE ORGANS AND HYPERTENSION IN SPONTANEOUSLY HYPERTENSIVE RATS. I. EFFECTS OF HYPOPHYSECTOMY, ADRENALECTOMY, THYROIDECTOMY, NEPHRECTOMY AND SYMPATHECTOMY ON BLOOD PRESSURE. Jpn Heart J. 1963 Sep;4:443–461. doi: 10.1536/ihj.4.443. [DOI] [PubMed] [Google Scholar]
- Fisher J. W., Langston J. W. Effects of testosterone, cobalt and hypoxia on erythropoietin production in the isolated perfused dog kidney. Ann N Y Acad Sci. 1968 Mar 29;149(1):75–87. doi: 10.1111/j.1749-6632.1968.tb15139.x. [DOI] [PubMed] [Google Scholar]
- JACOBSON L. O., GOLDWASSER E., FRIED W., PLZAK L. Role of the kidney in erythropoiesis. Nature. 1957 Mar 23;179(4560):633–634. doi: 10.1038/179633a0. [DOI] [PubMed] [Google Scholar]
- OKAMOTO K., AOKI K. Development of a strain of spontaneously hypertensive rats. Jpn Circ J. 1963 Mar;27:282–293. doi: 10.1253/jcj.27.282. [DOI] [PubMed] [Google Scholar]
- WALDMANN T. A., BRADLEY J. E. Polycythemia secondary to a pheochromocytoma with production of an erythropoiesis stimulating factor by the tumor. Proc Soc Exp Biol Med. 1961 Nov;108:425–427. doi: 10.3181/00379727-108-26957. [DOI] [PubMed] [Google Scholar]