Carotid sinus baroreceptor (CSB) (CSB)

The Carotid sinus baroreceptor (CSB) is a specialized mechanosensitive sensory nerve ending located within the adventitia of the carotid sinus at the bifurcation of the common carotid artery (StatPearls, NBK545247). It functions as a high-pressure sensor that detects changes in arterial wall stretch, translating mechanical strain into electrical signals through mechanosensitive ion channels, primarily PIEZO2 (Nature, 2018, 562:586-590). These afferent signals are transmitted via the Hering's nerve and the glossopharyngeal nerve to the nucleus tractus solitarius in the medulla oblongata. This pathway initiates the baroreflex, a vital homeostatic mechanism that regulates blood pressure by modulating the balance between sympathetic and parasympathetic nervous system activity. In clinical conditions such as chronic hypertension and heart failure, the sensitivity of these baroreceptors is often impaired, leading to sustained sympathetic overactivity (JACC, 2015, 65:21). While systemic drugs like digoxin are known to sensitize these receptors to enhance their inhibitory effect on the heart, they are also the direct anatomical target for Baroreflex Activation Therapy (BAT) devices designed to treat resistant hypertension (Circulation, 1991, 83:420-428).

Other names

Carotid baroreceptorPressoreceptorHigh-pressure baroreceptor

Sensitization or direct activation of mechanosensitive nerve endings to increase afferent signaling to the brainstem, resulting in decreased sympathetic tone and increased parasympathetic activity.