Arterial baroreceptor input contributes to long-term control of blood pressure.

A little more than three decades ago, there was little doubt that baroreceptors were crucial for both the short-term and long-term control of mean arterial blood pressure (MAP). Then, in 1970 it was reported that baroreceptors reset completely within 48 hours in hypertensive rats. Three years later, it was reported that MAP was near normal in dogs with both aortic and carotid baroreceptors denervated based on continuous measurements, thus discrediting numerous reports of denervation-induced hypertension. These two observations quickly led to a reevaluation of the importance of baroreceptor input in long-term control mechanisms. Finally, a consensus emerged that baroreceptor input could not be involved in long-term control of MAP, and this conclusion can be found in all modern textbooks of physiology used in the instruction of medical students. However, recent experimental observations have challenged the conclusion that baroreceptor input plays no role in the long-term control of MAP. In this article, the principal arguments against baroreceptor involvement in long-term control of MAP are summarized, and the new findings that suggest that a reappraisal of our current concept is required are reviewed.