BLOOD NOW RESPONSES TO INTRAARTERIAL ACETYLCHOLINE IN MAN - EFFECTS OF BASAL NOW AND CONDUIT VESSEL LENGTH

1. Acetylcholine relaxes human resistance vessels and releases nitric oxide and other factors from the endothelium. Comparison of responses to acetylcholine with those to an endothelium-independent vasodilator (such as nitroprusside) forms the basis of the so-called acetylcholine test of endothelial function. However, when this test is applied in v ivo by intra-arterial infusion, the metabolic instability of acetylcho line may result in differential responses to these drugs arising from anatomical rather than functional differences.