Article by Charlie Fidelman, Montreal Gazette
Montreal researchers have found a new role for cannabinoids. The active ingredient in marijuana — which is also naturally present in the human body — seems to improve night vision in vertebrates.
The study by a multidisciplinary team including researchers from the Montreal Neurological Institute looked at changes in tadpole retinas after exposure to cannabinoids.
“We didn’t believe what we were seeing — exactly the opposite of what we expected,” saidneurologist Ed Ruthazer, of the Montreal Neurological Institute of McGill University, and the paper’s senior author.
Researchers expected to find the drug would inhibit the tadpoles’ retinal ganglion cells (RGCs), which are responsible for transmitting information about light detection from the eye to the brain.
“But the cannabinoids were increasing the excitability of cells in the eye that connects to the brain,” Ruthazer said. One class of cannabinoid receptor, known as CB1, fired at higher frequencies allowing the tadpoles swimming in a petri dish to see better and flee predators in low light conditions, he explained.
Published on Aug. 8 in the journal eLife, a peer-reviewed open-access scientific journal for biomedical and life sciences, the study adds to the understanding of cannabinoids and brain function.