MARIJUANA-LIKE CHEMICAL HELPS RELIEVE COUGHS - STUDY

LONDON, Nov 1 (Reuters) - A team of international scientists have
discovered why marijuana causes coughing in some asthma patients but
not in others in a finding that could lead to better respiratory
treatments with fewer side effects.

In a report in the science journal Nature on Wednesday, researchers
from Italy, Hungary and the United States identified a cannabis-like
chemical in the body called anandamide and showed how it influences
the airways in the lungs.

In animal studies, anandamide, which is similar to active ingredients
in marijuana called cannabinoids, inhibits coughing caused by an
irritant when the muscles in the lungs are tensed, but if the airways
are relaxed it can cause a coughing spasm.

A cannabinoid receptor molecule, a chemical doorway into the cell,
found on nerve endings in the lungs seems to control both reactions.

"We think that by targeting cannabinoid receptors in the upper airways
we can control coughs in a number of conditions," Daniele Piomelli, a
pharmacologist at the University of California, Irvine, said in a
telephone interview.

"That's important because most treatments currently available
basically act on the brain cough centre, a small region of the brain
that is the target for codeine and similar drugs."

Highs And Lows

New treatments targeting the receptor molecule would be an alternative
to codeine and other opiates, which produce serious side effects
including addiction.

In an inhaler form, a treatment would act directly on the lungs,
thereby eliminating many of the unwanted side effects of codeine and
similar drugs.

Piomelli and scientists from The Institute of Experimental Medicine in
Budapest, the University of Naples in Italy and the University of
Washington in Seattle, who contributed to the research, hope to begin
human tests soon.

"Hopefully we will be doing that in the not-too-far future," Piomelli
said.

If the research goes well and produces the same results as the animal
studies, the scientists hope new treatments for coughs caused by
asthma and other respiratory illnesses could be available in a few
years.

"We're very excited about the possibilities and would like to push it
forward," he said.

Marijuana-Based Drugs For A Variety Of Ailments

Scientists have been studying marijuana with the idea of developing
new treatments for a variety of conditions ranging from asthma and
stroke to cancer and spinal cord injuries and nerve damage.

Medical studies have shown that it is useful for pain relief, to
control nausea and vomiting associated with chemotherapy treatment and
to reduce anxiety.

"We tried to understand the cannabis-like system in the body because
we think it is a source for many different potential medicines. But in
order for us to develop these medicines, we need to understand how the
physiology works," said Piomelli.