STUDY GETS MONKEYS HOOKED ON THC

NEW YORK (AP) -Monkeys repeatedly dosed themselves with the main active
ingredient of marijuana in a recent federal study. The researchers say that
result emphasizes the idea that people can get hooked on pot and may provide
a new way to test therapies.

Lab animals will actively dose themselves with most drugs abused by people,
but marijuana has been an exception, said researcher Steven Goldberg of the
National Institute on Drug Abuse, called NIDA.

Some people might interpret that as suggesting it has little potential for
addiction, he said. But the new work found that squirrel monkeys repeatedly
pushed a lever to get injections of the marijuana ingredient THC, Goldberg
and colleagues report in the November issue of the journal Nature
Neuroscience.

The animals pushed the lever about as much as other monkeys did to get
cocaine, but Goldberg said that does not necessarily mean marijuana is as
addictive as cocaine in people.

NIDA says marijuana causes compulsive and often uncontrollable craving and
use, despite health and social consequences, and so is addictive.

Not everybody agrees.

"This drug is not addicting. Clinical experience says that," said Dr. Lester
Grinspoon, a Harvard Medical School emeritus professor of psychiatry.

The monkey study doesn't prove otherwise, said Grinspoon, who is chairman of
the board of the NORML Foundation, which promotes medical use of marijuana
and ultimately its legalization.

In Goldberg's experiment, four squirrel monkeys sat through hour-long test
sessions once a day with a tube attached to a vein. When a green light
turned on, they could push a lever 10 times to get a THC injection.

They gave themselves up to 30 injections per session, vs. one to four when
the tube delivered only water.

In proportion to their body size, the monkeys got about the same dose of THC
per injection that a person does with each puff from a marijuana cigarette.
The monkeys didn't show any sign of being sedated, Goldberg said.