Calcitonin gene-related peptide (CGRP) causes redistribution of blood flow in humans.

In normal human subjects ( n=6), blood flow in the common carotid artery, assessed with an ultrasonic duplex-scanning unit, was increased up to 152% of basal levels by 60-min infusions of human calcintonin gene-related peptide I (αCGRP) 80 pmol·kg·h, but it was not affected by 20 pmol·kg·h CGRP or 88 pmol·kg·h human calcitonin. In the superior mesenteric artery, on the other hand, blood flow was reduced by 80 pmol·kg·h CGRP to 58% of the basal level, but not by 20 pmol·kg·h CGRP or with 88 pmol·kg·h calcitonin. Blood flow in the abdominal aorta remained largely unchanged under the same conditions. Skin blood flow, assessed by a laser Doppler unit, was increased up to 682% of the basal level by 80 pmol·kg·h CGRP, but not by 20 pmol·kg·h CGRP or calcitonin. Thus CGRP increased regional blood flow to the brain and the skin at the expense of the gastrointestinal tract. [ABSTRACT FROM AUTHOR]