The Carotid Body: A Tiny Structure with Many Roles.

Over the last century, the structure of the mammalian carotid body (CB) has repeatedly been studied, and our present understanding of its normal morphology is comprehensive. It has been demonstrated that the CB has an intricate internal structure and a remarkable ability to release a wide variety of neurotransmitters and neuromodulators in response to different chemical stimuli. The advances in modern cellular/molecular biological methods and newly developed single-cell electrophysiological techniques have provided an additional insight into the precise working mechanisms and roles of the CB in health and disease. Emerging experimental evidence has also shown that the CB exhibits an extraordinary structural and functional plasticity as a consequence of various environmental stimuli. Lately, the CB has attracted much clinical interest because its dysfunction relates to a number of cardiovascular and respiratory disorders. Expanding knowledge about the pathophysiological mechanisms that alter the CB cell function would certainly help to facilitate the translational research. Recent progress in cell fate experiments has further revealed that the CB is a neurogenic center with a functionally active germinal niche. This may lead to the development of promising new candidate therapies to combat these diseases and improve the quality of human life. Thus, the CB has entered the twenty-first century with its actual designation.