Journal of Applied Physiology, Vol 41, Issue 6 865-870, Copyright © 1976 by American Physiological Society
Acute response to venous distention in the extremity of the dog
M. C. Conrad
Aortic and vena caval pressures, right and left iliac flows. and pedal
small artery and small vein pressures were recorded in mongrel dogs prior
to and for 90 min following ligation of the right iliac, femoral, medical
saphenous, and lateral saphenous veins. Total, arterial, small vessel and
venous resistances were calculated. Measurements were repeated following
alpha-receptor blockade (phenoxybenzamine) and perfusion of the extremities
with a calcium chelator (EGTA). Results indicated that venous ligation
resulted in constriction of small vessels in both the occluded and
contralateral extremities and constriction of veins in the occluded
extremity only. Relative responses of right and left vascular bed to
alpha-blockade and EGTA perfusion suggested that small vessels were
constricted bilaterally by enhanced sympathetic stimulation and that veins
and small vessels were constricted on the occluded side in response to a
local myogenic stimulus.
