SCIENCE NOTEBOOK

Compiled from reports by Curt Suplee, John Schwartz and Rob Stein.

BIOLOGY: Taking a Leaf From Marijuana's Effect New research suggests
that scientists may be able to develop a powerful new painkiller
modeled on the active ingredient in marijuana.

In rats, a drug that mimics delta-9-tetrahydrocannabinol, the main
active ingredient in marijuana, deadens pain like morphine,
researchers at the University of California at San Francisco showed.
The findings indicate that marijuana-like drugs kill pain without
producing the side effects of morphine.

"Given their unique side-effect profile (for example, cannabinoids
increase appetite, whereas opioids can cause nausea and respiratory
depression), cannabinoids may be useful in improving the treatment of
pain," Ian D. Meng and colleagues write in the Sept. 24 Nature.

Rats given a synthetic cannabinoid kept their tails near a heat source
longer than rats that did not get the drug. And when the researchers
shut down a region of the rats' brain known as the rostral
ventromedial medulla, which is affected by drugs like morphine, they
no longer had an insensitivity to pain.

Copyright 1998 The Washington Post Company

Checked-by: Rich O'Grady