AJP - Regulatory, Integrative and Comparative Physiology, Vol 243, Issue 1 142-R146, Copyright © 1982 by American Physiological Society
Neural control of vasomotion in rabbit ear is impaired during desynchronized sleep
C. Franzini, T. Cianci, P. Lenzi and P. L. Guidalotti
In a warm environment the skin vessels of the rabbit ear, dilated during
synchronized sleep (SS), reduce their caliber during desynchronized sleep
(DS). In a cold environment the ear skin vessels, constricted during SS,
increase their caliber during DS. These vascular changes contrast with
thermoregulatory homeostasis. They can be accounted for by the decrease in
both local transmural pressure and sympathetic vasoconstrictor discharge
accompanying the DS phase. A decrease in local transmural pressure prevails
in a warm environment and a decrease in sympathetic discharge in a cold
environment. Accordingly, the vessel caliber decreases in the heat and
increases in the cold. The results of the sympathetic denervation of the
ear and of the alpha-receptor blockade confirm the passive nature of
vascular changes in the rabbit ear during DS.
