Combined transport of water and ions through membrane channels.
The coupling of ion and water flow through membrane channels is under dispute. Among all human aquaporins only aquaporin-6 exhibits ion channel activity. Whether aquaporin-6 functions also as a water channel cannot yet be determined with confidence. Similarly, a comparison of single-channel water permeabilities from ion channels and aquaporins suggests that ion channels may play a secondary role as water channels. However, the fraction of absorbed fluid that crosses epithelial ion channels still remains to be determined.
Pohl
Peter
P
Forschungsinstitut für Molekulare Pharmakologie, Robert-Rössle-Str. 10, D-13125 Berlin, Germany. pohl@fmp-berlin.de
D000818:Animals; D020346:Aquaporins / Q000737:chemistry* / Q000378:metabolism*; D006801:Humans; D015640:Ion Channel Gating / Q000502:physiology; D014867:Water / Q000737:chemistry* / Q000378:metabolism*
D020346:Aquaporins; D014867:Water