Credit: Cell, Bin Yang & Viviana Gradinaru/Caltech

The whole body of a rodent can be rendered transparent for imaging, without damaging cells and proteins.

Previous techniques for making tissue transparent have tended to work only on specific organs, such as the brain. A team led by Viviana Gradinaru at the California Institute of Technology in Pasadena tweaked an existing technique that stabilizes tissue and strips out light-blocking lipids with a cocktail of chemicals pumped through a dead rodent's circulatory system. Crucially, the process maintained the integrity of mouse neurons, kidney structures (pictured) and other tissue.

After one week for mice and two for rats, the brain and internal organs were clear and could be imaged under a microscope. The technique could allow researchers to see connectivity between the brain and other organs.

Cell (2014)