ENHANCED CONTRACTION TO NORADRENALINE, SEROTONIN AND NERVE STIMULATION BUT NORMAL ENDOTHELIUM‐DERIVED RELAXING FACTOR RESPONSE IN SKIN SMALL ARTERIES IN HUMAN PRIMARY HYPERTENSION

Abstract

1. We measured the reactivity of 2 mm long ring segments of human resistance arteries dissected from gluteal skin biopsies and mounted on wires in a Mulvany‐Halpern myograph for recording isometric force. Arteries were taken from eight normotensive (N) volunteers (average age 46 years, blood pressure 126/82 mmHg) and eight untreated hypertensives (H; average age 48 years, blood pressure 149/101 mmHg). 2. In small diameter arteries (internal diameter 500 μm), no response to acetylcholine was noted in either H or N arteries. The sensitivity to serotonin and angiotensin II was similar between these arteries but the EC50 to noradrenaline was less in H than in N arteries (ΔEC50= 0.61 ‐log mol/L)..