Cardiac and other visceral afferents

Visceral afferents are responsible for both conscious and unconscious sensory transduction and are integral to autonomic reflexes at local, spinal, and central levels. The majority of afferent cell bodies are located in the nodose ganglia (vagal) or dorsal root ganglia (spinal afferents) and robustly innervate the heart, lungs, and gastrointestinal tract. These sensory afferents are physiologically involved in the regulation of blood pressure, cardiac mechanical and electrophysiological activity, breathing patterns, and gut motility, among others. Sympathetic activation has been implicated in the pathogenesis of multiple cardiovascular disorders, and is, in part, related to depressed sympatho-inhibitory reflexes at the level of the heart. Moreover, afferent activation at the level of the kidneys and renal vasculature has also been implicated in the pathogenesis of hypertension and heart failure. Given the role of neurohormonal activation and neurogenic substrates in cardiovascular disease, therapies targeting abnormal function of afferents remain an area of intensive research.