ABSTRACT

Aquaporins (AQP) are a family of small integral proteins (measuring 28-to-32 kD) that are found on the surface of cell membranes. They constitute a molecular system whose principal function consists in facilitating the transport of water through the cell membranes in response to osmotic gradients. Up to the present, 13 sub-types have been identified, distributed in different human organs, including the kidneys, brain, eyes, and respiratory system. Existing experimental models have succeeded in determining the expression and function of AQP in the respiratory system; however, ascertaining the potential clinical implications that may derive from our understanding of these structures will require additional explorations in future studies. Current scientific evidence suggests that AQP play a central role in the physiopathology of clinical entities related to osmotic imbalance, however, recent data suggest that they also appear to be involved significantly in processes of cell migration as well. The purpose of this review is to simplify the available information related to the functioning and participation of AQP in the respiratory system.

KEYWORDS

Aquaporins, water channels, respiratory physiology, pleural effusion, acute lung injury, cancer.

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