"This study points to a potentially new kind of therapy for Parkinson's disease," said senior author Robert Malenka, MD, PhD, at Stanford University’s School of Medicine. "Of course, it is a long, long way to go before this will be tested in humans, but nonetheless, we have identified a new way of potentially manipulating the circuits that are malfunctioning in this disease."

Malenka and postdoctoral scholar Anatol Kreitzer, PhD, the study's lead author, combined a drug already used to treat Parkinson's disease with an experimental compound that can boost the level of endocannabinoids in the brain. When they used the combination in mice with a condition like Parkinson's, the mice went from being frozen in place to moving around freely in 15 minutes.

But Kreitzer and Malenka cautioned that their findings don't mean smoking marijuana could be therapeutic for Parkinson's disease. The treatment used on the mice involves enhancing the activity of the chemicals where they occur naturally in the brain. "That is a really important difference, and it is why we think our manipulation of the chemicals is really different from smoking marijuana."

"The cool new finding came when we thought to use drugs that boost the activity of endocannabinoids." Based on prior knowledge of endocannabinoids and dopamine, they speculated that the two chemicals were working in concert to keep the inhibitory pathway in check. When they added a drug that slows the enzymatic breakdown of endocannabinoids in the brain the results were described as striking: "The dopamine drug alone did a little bit but it wasn't great, and the drug that targeted the enzyme that degrades endocannabinoids basically did nothing alone," Kreitzer said. "But when we gave the two together, the animals really improved dramatically."

MEDICA.de; Source: Stanford University