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A drug that boosts levels of the brain's own "bliss" chemical can help reverse symptoms of depression in rats, US and Italian researchers reported yesterday.
The drug helps maintain high levels of a compound called anandamide, named after the Sanskrit word for "bliss", which is chemically similar to the active ingredient in marijuana.
"These findings raise the hope that the mood-elevating properties of marijuana can be harnessed to treat depression," said Daniele Piomelli, director of the Centre for Drug Discovery at the University of California, Irvine, who led the study.
"Marijuana itself has shown no clinical use for depression. However, specific drugs that amplify the actions of natural marijuana-like transmitters in the brain are showing great promise," he added in a statement.
Piomelli's team used a drug patented this year, called URB597. It interferes with another compound called fatty acid amide hydrolase or FAAH, which in turn breaks down anandamide.
Dialing back FAAH makes more anandamide available in the brain, Piomelli said.
Writing in the journal Biological Psychiatry, Piomelli and colleagues said they gave URB597 to chronically stressed rats, which act in a way similar to depressed people.
After five weeks of treatment, treated rats acted more like unstressed rats, Piomelli's team said.
Piomelli, who patented URB597 with colleagues at the Universities of Urbino and Parma in Italy, licensed the drug to European drugmaker Organon BioSciences.
He said Organon will begin clinical studies on the drug in 2008.
Organon is a unit of Dutch chemical group Akzo Nobel, which is in the process of selling it to Schering-Plough Corp.
- REUTERS