Journal of Applied Physiology, Vol 39, Issue 5 702-706, Copyright © 1975 by American Physiological Society
Localization of the effective thermosensitive site in the preoptic region of the ox
D. T. Calvert and J. D. Findlay
These studies were carried out using chronically implanted thermode probes
in conscious oxen at 15 degrees C air temperature. The probes were perfused
with water either 4 degrees C above or 5 degrees C below resiting
hypothalamic temperature and the thermoregulatory response measured by the
change in auditory meatal temperature during the perfusion periods of 25 or
40 min duration, respectively. The anatomical position of the probes was
known relative to the third cerebral ventricle in each animal. The
thermosensitive area of the ox anterior hypothalamic/preoptic region was
shown to be highly localized in a position corresponding to the posterior
part of the area preoptica. The same area was responsible for both warm and
cold sensitivity, the warm sensitivity being approximately three times
greater than the cold.
