Peripheral and Renal Venous Plasma Renin Concentration in Hypertensive Patients with Unilateral Renal or Renovascular Disease

Renal venous catheterization was carried out in a consecutive series of 32 hypertensive patients with unilateral renal or renovascular disease. Plasma renin concentration (PRC) was measured in systemic and renal venous blood with a method allowing the expression of results in terms of Goldblatt Units. Blood samples were collected before and after intravenous injection of furosemide (0.33–0.66 mg/kg body weight).Systemic PRC was elevated in ten out of 19 patients with lesions of the main renal artery. Only one out of 11 patients with unilateral parenchymal renal disease had elevated systemic PRC. A unilateral significant veno-arterial renin concentration difference over the affected kidney was found in eight out of 15 patients with renal artery stenosis and in three, out of 11 patients with unilateral parenchymal renal disease. In patients with renal artery stenosis, a close association was found between increased systemic PRC and renal venous PRC-ratios <1.8. Furosemide led to an increased release of renin from the majority of kidneys with a considerable pre-injection veno-arterial difference.Estimated renin secretion rates (ERSR) were calculated on the basis of measurements of GFR, determinations of fractional distribution of blood flow between the two kidneys, and veno-arterial renin differences across the individual kidney. The range of ERSR was 1.400–100.000 Goldblatt Units × 10-6 per minute. A good correlation was demonstrated between total ERSR and systemic PRC.