Zebrafish are easily blinded. If they are in total

darkness for several days and then exposed to very bright light, all the photoreceptors in their retinas are destroyed.

Due to their robust regenerative ability, however, their eyes recover in just 28 days. When the biologists injected drugs that kept GABA concentrations in the retinas of newly blinded fish at a high level, they found that it suppressed the regeneration process.

On the other hand, when they injected an enzyme that lowers GABA levels in the eyes of normal fish, they found that the Muller glia began dedifferentiating and proliferating, the first stage in the regeneration process.

"Our theory is that a drop in GABA concentration is the trigger for regeneration. It initiates a cascade of events that includes the activation of the Muller glia and the production of various growth factors that stimulate cell growth and proliferation," said Patton.

"If we are correct, then it might be possible to stimulate human retinas to repair themselves by treating them with a GABA inhibitor," Patton added.

(This article has not been edited by DNA's editorial team and is auto-generated from an agency feed.)