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

## TL;DR

This study identifies TRPV4, a type of ion channel, in specific cells of the human carotid body, suggesting a potential role in its sensory functions.

## Contribution

The novel finding is the first report of TRPV4 expression in the human carotid body.

## Key findings

- TRPV4 is present in about 65–68% of chemoreceptor type I cells in the human carotid body.
- TRPV4 is also found in a subpopulation of type II supporting cells and nerve terminals in the carotid body.

## Abstract

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.