Effect of stimulation of aortic nerves in rabbits under hyperthermia.

Stimulation of the aortic nerves was studies in 20 rabbit in relation to increasing body temperature. Depressive reaction was not changed within temperature range of 38--42 degrees C. This reaction was abolished when the temperature exceeded 42 degrees C, in spite of the fact that heating was discontinued and the body temperature returned to its initial value. A complete loss of the reaction or trace depressive reaction, observed when the temperature exceeded 42 degrees C, could be due to thermal inactivation of the neurons in the cardiovasomotor centre.