Comparison of Blood Flow in Normally Innervated and in Sympathectomized Legs of Dogs After Exposure to Cold

¹ From the Departments of Physiology and Orthopedic Surgery, State University of Iowa, Iowa City, Iowa

Volume blood flow was measured by a technique of venous occlusion plethysmography in hind legs of dogs with intact innervation and in sympathectomized legs during and following rewarming after exposure to cold. The area of the leg from the level of the knee down was immersed in an alcohol dry-ice mixture at –4°C for 3 1/2 hours. During and for some time after rewarming there occurred an increase in blood flow in exposed hind legs with intact innervation but no change occurred in sympathectomized legs after their exposure to cold. These findings point to some type of vasomotor dysfunction or impairment as being responsible for the increase in blood flow in normally innervated legs following their exposure to cold.