Molecular Mechanism May Regulate Eye Pressure


Scientists in the University of Arizona Department of Physiology have identified a potential molecular mechanism that may hold the key to understanding how pressure is regulated in the eye. Funded by a $2.3 million 5-year grant from the National Institutes of Health National Eye Institute, this research could help to develop future treatments for glaucoma and other diseases.

In response to this major health issue, Nicholas Delamere, PhD, professor and head of the Department of Physiology at the University of Arizona College of Medicine Tucson, and his research team have discovered a specific “mechanosensitive ion channel,” TRPV4, which they believe senses and helps regulate pressure inside the eye. Mechanosensitive channels (MS channels) are proteins found in most cell membranes that open a conductance pore in response to mechanical stress.

The size of each cell in the body is determined by the regulation of the amount of fluid that flows in and out of the cell itself. Cells continually swell and shrink to maintain their appropriate dimensions. Pressure-sensing mechanisms control the correct amount of fluid in each cell, but exactly what signal tells the cell to switch from input to output of these fluids to keep the precise amount of pressure remains a mystery, Dr. Delamere explained.

“Like a cell, the eyeball needs the correct amount of fluid formation and drainage to keep its proper size to stay plump and healthy,” he said. “We still don’t really know how the eye knows to keep the pressure balanced on a safe level.”