Pressure dependence of the carotid sinus elastic modulus in the dog.

The effect of the mean intrasinusal pressure upon the dynamic elastic modulus of the carotid sinus was examined in seven dogs. In all dogs the carotid sinus elastic modulus was a direct function of the mean intrasinusal pressure, measured at the lingual artery. The carotid sinus thus appears to become progressively stiffer with increasing pressure with a consequent reduction in oscillatory strain. This reduction of oscillatory stimulation of the carotid sinus mechanoreceptors acts so as to limit the maximum gain of the carotid sinus reflex to the region of the closed loop operating pressure.