The carotid body, a small cluster of chemoreceptor cells located at the bifurcation of the common carotid artery, plays a vital role in maintaining oxygen (O2) homeostasis. It acts as the body’s primary sensor for detecting changes in blood gas composition, particularly decreases in O2 tension (hypoxia), and responds by stimulating ventilation to increase oxygen supply. Decades of research have unraveled the intricate mechanisms underlying carotid body chemoreception, but significant questions remain. This review delves into the current understanding of this complex physiological process, highlighting recent discoveries and ongoing debates.

Early work by Carl and Ulf von Euler in the 1930s established the carotid body as the key peripheral chemoreceptor for hypoxia sensing. Subsequent studies identified the presence of two main cell types – glomus type I (chromaffin) cells and glomus type II (sustentacular) cells – and their potential roles in chemosensory transduction. Building upon this foundation, research has progressed to explore the intricate signaling pathways, cellular interactions, and physiological adaptations that orchestrate the carotid body’s response to hypoxia.