Using marijuana-like chemicals in combination with an existing drug has the potential to improve the treatment of Parkinson's disease, according to a new study.

Researchers said that mice which were administered the drub combo were able to move freely within 15 minutes after administration. Writing in the February 8 issue of the journal Nature, the scientists warned that similar effects may not be seen after smoking cannabis.

The study conducted on genetically altered mice focused on naturally occurring chemicals called cannabinoids. These chemicals contain several molecules found in marijuana. Lead researcher Anatol Kreitzer said that the study concentrated only on those cannabinoids capable of releasing the neurotransmitter dopamine.

Dopamine is a key chemical in Parkinson's Disease since its lack is responsible for the tremors or the movement issues associated with the condition. In effect, Kreitzer's team uses the marijuana-like compounds to activate the cells that release dopamine in the brain.

When the chemical is released, the stiffness and rigidity in the mice vanished and they were able to move freely, the researchers reported. Kreitzer and Dr. Robert Malenka, professor in psychiatry and behavioral sciences at Stanford targeted a region of the brain called the striatum.

This region is implicated in Parkinson's disease as well as several other neurological disorders. "This particular part of the brain doesn't have any obvious anatomy," Kreitzer said. "If you just look at the cells, they all look alike. But it turns out that there are two specific circuits there involved in the control of movement -- a direct pathway that activates motion and an indirect pathway that inhibits motion."

In the mice, dopamine served as a trigger to initiate free movement. When dopamine was active, the mice had no problems in moving around, but when the chemical decreased in some pathways, the mice seemed frozen to a spot, the researchers said.

The researchers said that they used a compound being tested by Kadmus Pharmaceuticals in combination with an existing Parkinson's drug called quinpirole for the treatment.

Parkinson’s Disease is a disorder to the nervous system that is mainly caused by the depletion of dopamine from the brain. When levels of dopamine fall below normal, several nerve cells become very active and thus the uncontrolled movements seen in the disease.

Despite the success of this experiment, the researchers cautioned that there was still a long way to go before human trails can begin.

"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 acknowledged.