Medical Marijuana could be used to treat depression, according to a recent study.

Scientists at the University at Buffalo's Research Institute on Addictions (RIA) found that components of marijuana may be useful in reducing depression that results from chronic stress. They studied chronic stress and depression, with a focus on endocannabinoids, which are brain chemicals similar to substances in marijuana.

"In the animal models we studied, we saw that chronic stress reduced the production of endocannabinoids, leading to depression-like behavior," RIA senior research scientist Samir Haj-Dahmane said in a statement.

Endocannabinoids are naturally produced chemical compounds in the brain that affect motor control, cognition, emotions and behavior. As the name suggests, they are similar to the chemicals found in marijuana (Cannabis sativa) and its active ingredient, delta-9-tetrahydrocannabinol (THC).

"Chronic stress is one of the major causes of depression," Haj-Dahmane said. "Using compounds derived from cannabis -- marijuana -- to restore normal endocannabinoid function could potentially help stabilize moods and ease depression."

The next step in the research is to see if using a marijuana extract, cannabidiol (CBD), restores normal behaviors in the animals without leading to dependence on the drug.

The study, co-authored by Roh-Yu Shen, PhD, RIA senior research scientist, was funded by a grant from the National Institute of Mental Health. It appeared in the fall issue of the Journal of Neuroscience.

Medical marijuana remains a controversial issue. Although 23 states and the District of Columbia have approved its use to provide relief for health problems such as glaucoma, nerve pain, epilepsy, multiple sclerosis and nausea from chemotherapy, some experts are concerned that medical use of marijuana may normalize attitudes about the drug and lead people -- especially youth -- to believe it is completely safe.

The findings are detailed in the Journal of Neuroscience.