Plasma Immunoreactive Endothelin-1 in Experimental Malignant Hypertension

• Published in: Hypertension (Dallas, Tex. 1979) Tex. 1979), 1991-07, Vol.18 (1), p.93-100
• Main Authors: Kohno, Masakazu, Murakawa, Koh-ichi, Horio, Takeshi, Yokokawa, Koji, Yasunari, Kenichi, Fukui, Toshiki, Takeda, Tadanao
• Format: Article
• Language: English
• Subjects: Aging - metabolism; Analysis of Variance; Angiotensin II - pharmacology; Animals; Arterial hypertension. Arterial hypotension; Biological and medical sciences; Blood and lymphatic vessels; Blood Pressure - drug effects; Blood Urea Nitrogen; Body Weight - drug effects; Caffeine; Cardiology. Vascular system; Creatinine - blood; Desoxycorticosterone; Endothelins - blood; Experimental diseases; Humans; Hypertension, Malignant - blood; Hypertension, Malignant - chemically induced; Hypertension, Renovascular - metabolism; Kidney - metabolism; Male; Medical sciences; Phenylephrine - pharmacology; Radioimmunoassay; Rats; Rats, Inbred SHR; Rats, Inbred WKY; Renal Artery Obstruction - metabolism; Renin - blood; Systole
• ISSN: 0194-911X; 1524-4563
• DOI: 10.1161/01.hyp.18.1.93

We measured plasma concentrations of immunoreactive endothelin-1 (irET-1) in the prehypertensive and hypertensive phases in spontaneously hypertensive rats (SHR) and in malignant hypertension caused by deoxycorticosterone acetate (DOCA) -salt administration in SHR. We also measured concentrations of this peptide in another model of malignant hypertension, the two-kidney, one clip (2K1C) renovascular hypertensive rats chronically given caffeine. Plasma irET-1 concentrations in young (6-week-old) and mature (18-week-old) SHR did not differ from those of age-matched Wistar-Kyoto (WKY) rats. Four weeks of treatment with DOCA-salt increased blood pressure, blood urea nitrogen, serum creatinine, and plasma irET-1 in SHR but not in WKY rats. Eight weeks of DOCA-salt treatment further increased these values in SHR. Plasma irET-1 concentrations were not increased in the 2K1C rats. Six weeks of caffeine administration increased blood pressure, blood urea nitrogen, serum creatinine, plasma renin activity, and plasma irET-1 in the 2K1C rats but not in the sham-operated rats. Highperformance liquid chromatographic profiles of plasma extracts pooled from these rats with malignant hypertension showed that a major component of irET-1 eluted in the position of synthetic ET-1(1-21). Furthermore, acute hypertension induced by angiotensin II or phenylephrine did not affect the plasma irET-1 concentration in rats. The results suggested that the plasma ET-1 concentration is increased in rat models of malignant hypertension and that the high blood pressure itself is not the main factor involved in the increase of plasma ET-1. {Hypertension 1991;18:93-100