ASSESSMENT OF BLOOD-FLOW CHANGES AT MULTIPLE SITES IN RABBIT SKIN USING A (133)XENON CLEARANCE TECHNIQUE

(133)Xenon clearance represents a clinically useful method of measurin g local circulatory function in a variety of different tissues. The me thod detailed in this article describes how the (133)Xenon clearance t echnique can be adapted to simultaneously measure cutaneous blood flow , over a 15-min period, at a large number of skin sites within the sam e animal. Blood flow changes are measured in response to intradermally injected vasoactive test agents. The multisite injection plan which f orms part of the method removes bias due to site variations and genera tes data that can be analysed statistically. Results are expressed as the percent change in (133)Xenon clearance at test agent-injected site s as compared to control, saline-injected sites. The method provides a n accurate and time-efficient measure of skin blood flow. In the prese nt study, the technique is used to assess the receptor-mediated mechan ism of action of the vasodilator calcitonin gene-related peptide (CGRP ) and the possibility that the vasoconstrictor endothelin-1 acts to st imulate the release of vasodilator quantities of endogenous CGRP.