Network analysis of microcirculation of cat mesentery.

Abstract The modular configuration of the microcirculatory system in cat mesentery is subjected to a hydrodynamic network analysis assuming Poiseuillian dynamical behavior. Intravascular pressure, vessel pressure gradient, and wall shear stress are computed for an isolated module and presented as a function of vessel diameter, from arterial affluent to venous effluent. Computed and in vivo intravascular pressures show a marked disparity on the arterial side of the true capillaries and a fair agreement on the venous side. This is attributed to the effects of precapillary sphincter action and non-Newtonian rheological behavior. Computed pressure gradients based on a simple Poiseuillian relationship are approximately six times greater than those measured in vivo . By comparison of predicted and measured pressure gradients, the magnitude of maximum vessel wall shear stress is estimated to be on the order of 10 dyn/cm 2 .