Jet-lagged? Viagra may help
2007-05-22 07:23
Washington - The male impotence drug
Viagra may be useful for treating jet lag as well, according to
Argentine researchers who gave it to hamsters made to feel like
rodent globe-trotters.
The researchers manipulated the schedule of turning lights
on and off to induce jet lag in the laboratory animals, they
reported on Monday in the Proceedings of the National Academy
of Sciences.
Adult male hamsters given Viagra, also called sildenafil,
recovered from jet lag up to 50% faster than hamsters
that were not given it, the researchers said.
The scientists stopped giving the hamsters the highest dose
they had been using in the experiment due to a certain side
effect.
"However, we used the intermediate dose for the rest of the
experiments because at that dose animals did not manifest the
effects of sildenafil-induced penile erections," they wrote.
Flying across multiple time zones can confuse one's
sleep-wake cycle, resulting in the condition called jet lag,
marked by insomnia, sleepiness and difficulty concentrating.
Researchers Patricia Agostino, Santiago Plano and Diego
Golombek of the Universidad Nacional de Quilmes in Buenos Aires
gave doses of Viagra to the hamsters at night, then switched on
bright lights six hours early to simulate eastbound flight.
They judged how well the hamsters adjusted to the changes
by observing when they began running on exercise wheels.
The drug helped the rodents cope with jet lag only when
given before the equivalent of an eastbound flight, not the
reverse when they delayed turning on lights to simulate
westbound travel, the study found.
The researchers said the findings suggested that Viagra
could be useful to help people cope with jet lag or shift work.
They said the dose needed for such uses could be lower than the
one used for treatment of erectile dysfunction.
Viagra interferes with an enzyme that lowers levels of a
naturally occurring compound that plays a role in the
regulation of the circadian cycle, the body's internal clock,
the researchers said.