Journal of Applied Physiology, Vol 58, Issue 2 376-383, Copyright © 1985 by American Physiological Society
Effect of cutaneous denervation of face and trunk on thermoregulatory responses to cold in rats
M. E. Heath
The effect of eliminating afferent input from cutaneous thermoreceptors of
the face and trunk on the ability of rats to regulate body temperature in
cool environments was studied. Thermoregulatory ability in a cool
environment was assessed first in a 25 degrees C environment and then
during slow (20 min) and rapid (5 min) reductions of ambient temperature
(Ta) to 15 degrees C by monitoring rate of heat production, rectal
temperature, and skin temperature on the back, ear, and tail. These
measurements were made in four rats while they were intact and during the 2
wk after cutaneous denervation. Rats were found to regulate body
temperature well even after the cutaneous nerves of the trunk and face were
sectioned. In eight rats the metabolic curve was determined before and 7-10
days after cutaneous denervation. Although the minimal resting metabolic
rates did not differ in the two conditions, the lower critical temperature
was significantly elevated from 26.8 to 28.9 degrees C and the rate of rise
in metabolic rate per degrees celsius decrease in Ta was also significantly
higher after cutaneous denervation. It appears that the higher rate of heat
production is in compensation for an increase in the rate of heat loss in
denervated rats.
