The aortic bodies are one of several small clusters of peripheral chemoreceptors located along the aortic arch. They are important in measuring partial pressures of

oxygen Oxygen is a chemical element; it has chemical symbol, symbol O and atomic number 8. It is a member of the chalcogen group (periodic table), group in the periodic table, a highly reactivity (chemistry), reactive nonmetal (chemistry), non ...

and

carbon dioxide Carbon dioxide is a chemical compound with the chemical formula . It is made up of molecules that each have one carbon atom covalent bond, covalently double bonded to two oxygen atoms. It is found in a gas state at room temperature and at norma ...

in the

blood Blood is a body fluid in the circulatory system of humans and other vertebrates that delivers necessary substances such as nutrients and oxygen to the cells, and transports metabolic waste products away from those same cells. Blood is com ...

, and blood pH.

Structure

The aortic bodies are collections of

chemoreceptors A chemoreceptor, also known as chemosensor, is a specialized sensory receptor which transduces a chemical substance ( endogenous or induced) to generate a biological signal. This signal may be in the form of an action potential, if the chemorece ...

present on the aortic arch. Most are located above the aortic arch, while some are located on the posterior side of the aortic arch between it and the

pulmonary artery A pulmonary artery is an artery in the pulmonary circulation that carries deoxygenated blood from the right side of the heart to the lungs. The largest pulmonary artery is the ''main pulmonary artery'' or ''pulmonary trunk'' from the heart, and ...

below. They consist of glomus cells and sustentacular cells. Some sources equate the "aortic bodies" and " paraaortic bodies", while other sources explicitly distinguish between the two. When a distinction is made, the "aortic bodies" are

which regulate the

circulatory system In vertebrates, the circulatory system is a system of organs that includes the heart, blood vessels, and blood which is circulated throughout the body. It includes the cardiovascular system, or vascular system, that consists of the heart ...

, while the "paraaortic bodies" are the chromaffin cells which manufacture catecholamines.

Function

The aortic bodies measure partial gas pressures and the composition of arterial blood flowing past it. These changes may include: *

partial pressure. *

partial pressure. * pH (indirectly affected by carbon dioxide concentration). They are particularly sensitive to changes in pH. Aortic bodies are more sensitive detectors of total arterial blood oxygen content than the carotid body chemoreceptors, which are more sensitive detectors of the partial pressure of oxygen in the arterial blood. The aortic bodies give feedback to the medulla oblongata, specifically to the dorsal respiratory group, via the afferent branches of the

vagus nerve The vagus nerve, also known as the tenth cranial nerve (CN X), plays a crucial role in the autonomic nervous system, which is responsible for regulating involuntary functions within the human body. This nerve carries both sensory and motor fibe ...

(cranial nerve X). The medulla oblongata, in turn, regulates

breathing Breathing (spiration or ventilation) is the rhythmical process of moving air into ( inhalation) and out of ( exhalation) the lungs to facilitate gas exchange with the internal environment, mostly to flush out carbon dioxide and bring in oxy ...

and

blood pressure Blood pressure (BP) is the pressure of Circulatory system, circulating blood against the walls of blood vessels. Most of this pressure results from the heart pumping blood through the circulatory system. When used without qualification, the term ...

Clinical significance

paraganglioma A paraganglioma is a rare neuroendocrine tumour, neuroendocrine neoplasm that may develop at various body sites (including the head, neck, thorax and abdomen). When the same type of tumor is found in the adrenal gland, they are referred to as a p ...

, also known as a chemodectoma, is a

tumor A neoplasm () is a type of abnormal and excessive growth of tissue. The process that occurs to form or produce a neoplasm is called neoplasia. The growth of a neoplasm is uncoordinated with that of the normal surrounding tissue, and persists ...

that may involve an aortic body. Swelling can also occur. These bodies detect blood pressure and are involving in passing out and

Postural orthostatic tachycardia syndrome Postural orthostatic tachycardia syndrome (POTS) is a condition characterized by an abnormally large increase in heart rate upon sitting up or standing. POTS is a disorder of the autonomic nervous system that can lead to a variety of symptoms, ...

References

{{Arteries of chest Angiology Respiration

Structure

Function

Clinical significance

See also

References