STUDIES ON RENAL FUNCTION OF HYPERTENSIVE DISEASES (PART 2)

Abstract

(1) The author observed the relationship between renal function (renal clearance) and the level of blood pressure of 20 cases of hypertensive diseases with or without renal damage (with or without reduction of RPF) during the prolonged oral administration of hypotensive drugs and also determined the adequate level of the blood pressure by these patients.
(2) In the patients of whom RPF was decreased, it is found that the systolic or mean blood pressure should not permit to fall under the range 0 to 30% of the initial systolic or mean blood pressure. And the permittable fall degree of the blood pressure is settled by the grade of the general arterial sclerosis and not parallel to the reduction of RPF.
(3) By the hypertensive patients with marked renal damage, the permittable fall degree of the blood pressure is almost 0% of the initial blood pressure.
In the group with normal RPF, the permittable fall degree of blood pressure is 0 to 30% of the initial systolic or mean blood pressure. The permittable fall degree of the blood pressure is dependent on the level of the initial systolic blood pressure and the grade of the general arteriosclerosis. The permittable fall of the blood pressure in arteriosclerosis is slight against that of normotensive patients.
(4) By the patients whose permittable fall degree of the blood pressure is 0%, the reduction of RPF is almost parallel to the fall of the systolic blood pressure and the fall of the blood pressure is accompanied by a marked decrease of RPF and GFR and a marked increases of RVR.
(5) Of the patients whose blood pressure is permitted to fall, RPF, RVR and FF gradually return to the normal range accompanied with the fall of the blood pressure. But GFR changes not or increases slightly. If the blood pressure falls under the permittable fall degree, RPF decreases notably. These facts show us that the renal blood vessels of the hypertensive patients are still able to respond to the vasodilatatoric hemodynamic factors.
(6) There is no significant correlation between the permittable fall degree of the blood pressure, RPF, the initial blood pressure and the eyeground findings (Keith-Wagener's classification).