baroreceptor

Baroreceptors (or archaically, pressoreceptors) are stretch receptors that sense blood vessel deformation. The term "baroreceptors" is somewhat a misnomer, since they detect stretch rather than pressure directly. Increases in vessel diameter triggers increased action potential generation rates and provides information to the central nervous system. This sensory information is used primarily in autonomic reflexes that in turn influence cardiac output and vascular smooth muscle to influence vascular resistance. Baroreceptors act immediately as part of a negative feedback system called the baroreflex as soon as there is a change from the usual mean arterial blood pressure, returning the pressure toward a normal level. These reflexes help regulate short-term blood pressure. The solitary nucleus in the medulla oblongata of the brain recognizes changes in the firing rate of action potentials from the baroreceptors, and influences cardiac output and systemic vascular resistance.

Baroreceptors can be divided into two categories based on the type of blood vessel in which they are located: arterial baroreceptors and low-pressure baroreceptors (also known as cardiopulmonary or volume receptors).