AJP - Heart and Circulatory Physiology, Vol 234, Issue 4 384-H391, Copyright © 1978 by American Physiological Society
Neural control of nutritional and nonnutritional circuits in the dog hindpaw
C. H. Baker, D. L. Davis and E. T. Sutton
The neural control of blood flow and volume distribution between parallel
nutritional and nonnutritional circuits has been investigated in the
vascularly and neurally isolated dog hindpaw. Twelve paws were perfused by
controlled pressure and ten paws were perfused by controlled flow via the
cranial tibial artery. Venous outflow was measured and collected from the
lateral saphenous vein. The superficial and deep fibular nerves and the
tibial nerve were cut and individually stimulated, resulting in rates which
at least doubled the blood flow resistance. Vascular volume changes were
measured by injections of 51Cr-labeled red cells and 131I-labeled albumin.
Tissue volume changes were measured by plethysmography. Capillary diffusion
capacity was calculated from 86Rb extractions, and capillary filtration
coefficients were determined. Superficial fibular nerve and deep fibular
nerve stimulations apparently resulted in nonnutritional circuit
constriction with resulting blood flow redistribution to nutritional
circuits, possibly located in tissues other than the skin, e.g., adipose
tissue. Tibial nerve stimulation caused no redistribution of blood flow
between the two circuits presumably due to a uniform constriction of
arteries and small vessel segments.
