Pressoreceptor-autonomic oscillation; a probable cause of vasomotor waves.

I N A RECENT study of blood pressure response to intermittent flow and outflow of blood from the circulation (I), it was observed that after suddenly ceasing outflow and then beginning immediately the inflow of blood there usually followed in normal animals a series of damped oscillations in the blood pressure. This effect also occurred when the inflow of blood was suddenly stopped and was followed by outflow. However, following progressive stages of pressoreceptor denervation, these oscillations became less pronounced and were not demonstrable after total pressoreceptor denervation. Furthermore, after total spinal anesthesia, the waves were not evident. Therefore, the hypothesis was offered that these waves are due to pressoreceptor-sympathetic oscillation, and it was further supposed, because of similar periodicities of these waves and vasomotor waves found in dogs, that vasomotor waves might have the same origin. The present study adds additional observations in support of this hypothesis which was only briefly mentioned before.