[Small clusters of chemoreceptive and supporting cells located near the ARCH OF THE AORTA; the PULMONARY ARTERIES; and the coronary arteries. The aortic bodies sense PH; CARBON DIOXIDE; and oxygen concentrations in the BLOOD and participate in the control of RESPIRATION. The aortic bodies should not be confused with the PARA-AORTIC BODIES in the abdomen (which are sometimes also called aortic bodies). ( MSH )]