Perspiration dripping off a sweating brow can be easily seen, one drop at a time. Moisture within a biological cell is similar, although it happens on a smaller scale-one molecule at a time, in a channel through the middle of a protein embedded in the membrane surrounding the cell. That protein is called an aquaporin because it is a pore through which water passes in and out.
Science often happens the same way. Individual facts and findings pass one-by-one through the barrier between ignorance and knowledge. Occasionally, when a fact or finding is disproved, the flow is reversed.
This column describes aquaporins and outlines their 16-year history, with particular interest in an aquaglycero-porin found in human skin. Future columns will highlight the activities of several cosmetic manufacturers and their compositions to “stimulate” that aquaporin as a way to beautify human skin and hair. The current column will serve as an introduction and trace the step-by-step development of knowledge about aquaporins.