China Science

Lu,X; Kassab,GS

Abstract The vasoactivity of blood vessel is impaired by cardiovascular disease. Theex-vivo measurements of vasoactivity (wire and pressure myographs) have some inherent difficultiesin the characterization of pharmacodynamics and biomechanics. Here, we introduce a novel isovolumicmyograph which allows simultaneous measurement of both dynamic pressure and dimensional changesduring vasoconstriction or vasodilation. The principle of the isovolumic myograph is based on theutility of a hydraulically closed system with low compliance such that contraction against anincompressible fluid increases the pressure with the closed system while dilation decreases it. Wedemonstrate the sensitivity and utility of the new technique by the response of elastic (carotid),muscular (femoral) arteries, and femoral veins. The results show characteristic dynamic pressureresponse for each vessel type. Furthermore, our results show a Hill-type equation for thetension-velocity relation for smooth muscles as well as characteristic curves for each contraction.These novel findings for blood vessels will advance our knowledge of endothelium and vascular smoothmuscle mechanics and pharmacodynamics.

Keywords Blood Vessels; Vasoconstriction; Vasodilation

Annals of Biomedical Engineering
0090-6964, Volume 35, Issue 3, 2007, Pages 3-366