Relative Influence of Variations in Arterial and Venous Pressures on Resistance to Flow

¹ From the Department of Physiology, The Albany Medical College of Union University, Albany, New York

Arterial inflow and arterial and venous pressures were measured in the hind legs of dogs under conditions of variations in arterial or in venous pressures. When the arteriovenous pressure gradient was reduced by continuous or stepwise diminutions of arterial pressure, a curvilinear relationship, convex to the pressure axis, was observed when flow was plotted as a function of pressure gradient. With elevations of venous pressure, on the other hand, the pressure-flow curves were invariably linear over the range studied, and the extrapolated curve usually intersected the flow-axis at a low, positive value. The calculated value of resistance fluctuated markedly with variations in arterial pressure, but usually decreased only slightly with elevations of the venous pressure.

Note:
with the assistance of Harrison Zieske, Jr.