Transient Receptor Potential Vanilloid 4 (TRPV4) in the Human Carotid Body.

TRPV4 (transient receptor potential vanilloid 4) is a non-selective, multifunctional cationic channel that is expressed in numerous cells in the body. It can be activated by temperature, mechanical forces, and chemical and biochemical molecules. Functionally, TRPV4 participates in maintaining osmotic homeostasis, blood pressure, and hypoxic preconditioning. As far as we know, the presence of TRPV4 has never been reported in the carotid body despite the overlap that exists between some biological functions of TRPV4 and the physiology of the carotid body. In the present work, immunofluorescence associated with confocal laser microscopy, associated with quantitative analysis (area occupied by immunofluorescence), has been used to examine the occurrence of TRPV4 in the human carotid body. The results demonstrated the presence of TRPV4 in a subpopulation of chemoreceptor type I cells (approximately 65-68%), a subpopulation of type II supporting cells, and in nerve terminals in the human carotid body. Its function, if any, in this multisensory organ must be demonstrated, but it is in line with the functions attributed to the carotid body.