Reflex control of arterial compliance in rabbits

Reflex control of arterial compliance of the hind limb circulation has been assessed in rabbits. Brief interruption of constant flow perfusion of the hind limb produced a pressure decay that was determined by hind limb vascular resistance and arterial compliance; thus independent assessment of resistance was used to derive compliance. Experiments were performed under control conditions, during baroreceptor deactivation and during stimulation of water-sensitive receptors in the upper respiratory airways. Hind limb vascular resistance increased by more than 80% when either reflex was elicited, but parallel changes in the pressure decay curves were not observed. Instead a decrease in arterial compliance compensated for the elevation in vascular resistance. These results indicate that the dynamic elastic properties of the arterial tree can be reflexly controlled such that the time course of adjustments of arterial pressure is relatively independent of vascular resistance.