This magnified area of a mouse’s brain shows a severe injury. Scar tissue (highlighted in blue) surrounds the crushed optic nerve; the mouse is blind. Yet something remarkable is happening – nerve fibres are regenerating (shown in white) after researchers manipulated genes responsible for their growth. Job done – one might think – this mouse will see again! But laying new fibres is only half the story. These new fibres have no myelin, the waxy insulation needed to transmit signals from the eyes to the brain. Instead, the team injected the mouse with a drug called 4-AP, known to boost signals down poorly myelinated nerve fibres. Inspired by restoring the mouse’s sight, the team are working on a combination drug treatment that repeats this 'healing' process, and may one day be used to treat human nerve damage in conditions like glaucoma.
Written by John Ankers
BPoD stands for Biomedical Picture of the Day. Managed by the MRC London Institute of Medical Sciences the website aims to engage everyone, young and old, in the wonders of biomedicine. Images are kindly provided for inclusion on this website through the generosity of scientists across the globe.
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