(Ivanhoe Newswire) -- A new topical drug may be the answer to treating a common cause of vision loss.

Most diseases that cause loss of eyesight do so by increasing the permeability of blood vessels in the retina, which leads to fluid build-up. A molecule known as VEGF is the cause of the permeability. The condition can be treated, but it involves a series of painful injections into the eye of a molecule that antagonizes the VEGF which, in turn, stabilizes the blood vessels and stops the fluid build-up.

In a new study from the Scripps Institute, LaJolla, researchers ran tests on mouse and rabbit models to see if a small VEGF molecule inhibitor, that could be given topically, could accomplish the same thing.

The team, led by Martin Friedlander, used Src kinase -- a small molecular inhibitor of the signaling molecule associated with VEGF receptors. Whether it was injected or administered in an eye drop, the results were the same -- the fluid was eliminated.

The researchers then tested the inhibitor on mice and rabbits that didn’t have the Src kinase and the fluid accumulated, confirming their findings.

The authors of the study suggested further investigation to see if this new approach would benefit people with VEGF-induced blood vessel permeability. If it does, it will provide a way to treat vision threatening retinal fluid build-up without having to put patients through the painful injection process.

SOURCE: The Journal of Clinical Investigation, published online May 16, 2008