Leech neurons stained with voltage-sensitive dye.
New Fluorescent Dyes Highlight Neuronal Activity
Researchers at the University of California, San Diego School of Medicine have created a new generation of fast-acting fluorescent dyes that optically highlight electrical activity in neuronal membranes. The work is published in this week’s online Early Edition of the Proceedings of the National Academy of Sciences.
The ability to visualize these small, fast-changing voltage differences between the interior and exterior of neurons – known as transmembrane potential – is considered a powerful method for deciphering how brain cells function and interact.
However, current monitoring methods fall short, said the study’s first author Evan W. Miller, a post-doctoral researcher in the lab of Roger Tsien, PhD, Howard Hughes Medical Institute investigator, UC San Diego professor of pharmacology, chemistry and biochemistry and 2008 Nobel Prize co-winner in chemistry for his work on green fluorescent protein.
“The most common method right now monitors the movement of calcium ions into the cell,” said Miller. “It provides some broad indication, but it’s an indirect measurement that misses activity we see when directly measuring voltage changes.”