Response of peripheral blood flow was studied in subjects of various age groups with and without vascular disease. Under constant environmental conditions, the skin-muscle distribution of total flow to the lower extremity showed the following trend. In young healthy adults the muscles get a somewhat higher share; in elderly persons without vascular disease the distribution is about equal; in patients with nongangrenous obliterative arteriosclerosis the skin is favored over the muscle. Exercise increases total flow in all groups, but does not alter the distribution. Sympathectomy does not seem to influence response to exercise.

No abstract

Reflex vascular responses to cooling were studied in subjects with neurologic disorders, with a younger and an elderly "normal" group being used for comparison. By and large the responses were mirror images of those described for the Gibbon-Landis procedure. It was demonstrated that normal reflex responses to cooling as well as to warming are dependent upon the integrity of sympathetic innervation.