Reduction of Elevated Blood Pressure by Administration of Renal Extracts

A number of investigators have claimed beneficial results from the administration of renal extract. The earliest studies were those of Brown-Séquard and d'Arsonval¹in 1892 and of Meyer²the following year. These authors reported that nephrectomized animals were improved by their crude extracts. More recently it has been stated³that renal venous blood contains a substance which in animals causes diuresis, with reduction in the amount of sodium, chloride, potassium and urea in the blood. It has likewise been claimed⁴that extracts of the kidney cause diuresis and reduction of blood pressure in patients with nephritis. These therapeutic claims have not been confirmed nor have they received any serious consideration by competent authorities for a number of reasons. In the first place the hypotensive action claimed for these extracts has not been demonstrated in hypertensive animals. Secondly, the clinical data have not been convincing. In most