High resolution

Module 10: Figure carotid body chemoreception

Structure and function of the O2-sensing carotid body.

The panel on the left illustrates the functional organization of the four major components of the carotid body. O2 levels within the capillaries are sensed by the glomus cells that release a range of transmitters to excite the sensory nerve endings that then relay action potentials to the brain (yellow arrow). The signalling mechanisms that respond to metabolic acidosis (an increase in H+) or hypoxia (an increase in AMP) act to inhibit various K+ channels (see the text for further details). The location of the carotid body is shown in Module 10: Figure breathing control.