STUDIES ON COLLATERAL CIRCULATION. II. THERMIC CHANGES AFTER ARTERIAL LIGATION, SECTION OF SPINAL CORD OR POSTERIOR ROOTS AND GANGLIONECTOMY

Abstract

In the dog the lowered temp. of the feet produced by ligation of both external iliac arteries was not influenced by either transection of the spinal cord at the level of the 1st lumbar vertebra or transection of all the posterior roots on one side below the level of the 1st lumbar vertebra. Removal of the tributary sympathetic ganglia caused a prompt rise in temperature of the corresponding foot from room temperature to nearly that of the limb before ligation whether or not the spinal cord had been transected at the level of the 1st lumbar vertebra, and whether or not all posterior roots below this level on the corresponding side had been transected. These observations suggest that bulbar impulses and impulses communicating through the posterior roots below the level of the 1st lumbar vertebra play no appreciable part in the mechanism of the development of collateral circulation.