Brain and body temperatures in a panting lizard.

Panting in Sauromalus obesus is effective enough to keep deep body temperature (T(C)) and brain temperature (T(B)) below an ambient temperature of 45 degrees C for extended periods of time and has a greater cooling effect on the brain than on the remainder of the body. Six animals maintained T(C) and T(B) 0.9 degrees C (+/- 0.08 standard error) and 2.7 degrees C (+/- 0.2 standard error) respectively lower than the ambient temperature of 45 degrees C. It is possible that intracranial vascular shunts play a role in cranial cooling during panting.