DISCO INFERNO

Think Ecstasy Is Cool? You Couldn't Be More Wrong

Ecstasy may hit the people who take it with a potentially fatal double
whammynot only generating too much heat but also blocking a crucial way of
cooling down.

Most research into the effects of ecstasy has focused on heat production.
The drug increases the metabolic rate, and people who take it often dance
for hours. Both of these factors generate extra heat.

"The most dangerous thing is that body temperature climbs so rapidly," says
Rod Irvine, a pharmacologist at the University of Adelaide. "The membranes
start to break down, and you get renal failure. The brain swells and is
basically crushed."

The effects can be so extreme that William Blessing and his colleagues at
the Flinders Medical Centre in Adelaide wondered if the drug was also
affecting the body's ability to cool itself. And sure enough, when they
gave ecstasy to rabbits they found that it triggered severe constriction of
the blood vessels leading to the skin in their ears. "Blood flow drops to
near zero straight away," says Blessing. "The ear goes as white as a sheet."

Diverting blood to the skin is an important way of cooling down, so this
effect could contribute to the heatstroke that has killed over 100 people
worldwide since ecstasy hit the club scene 15 years ago.

A drug called clozapine restored blood flow in the rabbits' ears to near
normal. Clozapine blocks serotonin receptors in the brain, and is normally
used to treat schizophrenia. It can have severe side effects, so it would
not be ideal as an antidote to ecstasy, but Blessing suggests that similar
drugs could help people suffering from heatstroke. "Pharmaceuticals
companies are developing similar drugs without the side effects," says
Irvine. "They could be useful for treating ecstasy overdoses."

Blessing says it's not surprising that ecstasy affects blood flow as well
as mood, since similar parts of the brain regulate both functions. For
instance, recent studies in his lab suggest that blood flow to the skin is
controlled by the amygdala, a region of the brain that also plays a key
role in sexual behaviour, emotions and aggression. The link may have
evolved because animals mating or fighting are more likely to get injured,
says Blessing. Shutting down blood flow to the skin would help reduce bleeding.

Blessing presented the findings at a conference on the cardiovascular
system in Sydney last week.