THE MEASUREMENT OF CAPILLARY PRESSURE UNDER NATURAL CONDITIONS AND AFTER ARTERIOLAR DILATATION; IN NORMAL SUBJECTS AND IN PATIENTS WITH ARTERIAL HYPERTENSION AND WITH ARTERIOSCLEROSIS 1

Abstract

A study was made of the capillary pressure by the skin blanching method under natural conditions and in skin in which an arteriolar flare had been created by intradermal injection of histamine. The latter measurement was shown to have a quantitative relationship to arteriolar pressure. The average capillary pressure in 10 normal subjects1 was 9 mm. Hg; in 23 patients with arterial hypertension 12 mm.; and in 13 patients with senile arteriosclerosis 13 mm. The average arteriolar pressure in normal persons was 55 mm. Hg; in hypertensive patients 108 mm. and in arteriosclerotic patients 48 mm. Hypertension is due to an increased resistance in the vascular circuit. Evidence is presented that this resistance lies in the arteriolar portion, as it does in normal persons, and, in the absence of marked arteriosclerosis, is functional in character. Hypertension may be a compensatory phenomenon designed to maintain normal tissue oxidation through a normal capillary blood flow. Evidence for the basic difference between arterial hypertension and senile arteriosclerosis is given.