Viagra could become a panacea for jet-lagged travellers

Published on Tuesday 22 May 2007 00:16

SCIENTISTS have discovered a new potential use for Viagra - preventing jet-lag.

The anti-impotence drug helped hamsters recover more quickly when their sleep patterns were disrupted by bright light.

Viagra, the drug sildenafil, was originally developed for the treatment of high blood pressure and angina. The discovery that it combats erectile dysfunction was a happy and very lucrative accident.

Viagra interferes with an enzyme that reduces levels of a naturally occurring compound, cyclic guanine monophosphate (cGMP). In the brain, cGMP contributes to a signalling pathway that regulates the circadian cycle, the body's internal clock.

A team of Argentine scientists led by Dr Patricia Agostino, from the National University of Quilmes in Buenos Aires, injected hamsters with sildenafil at night.

Morning for the animals came six hours early, when they were illuminated with bright lights.

The researchers noted how the rodents coped with the change by observing how soon they began running in their exercise wheels.

Viagra-boosted hamsters recovered from their "jet-lag" 25 per cent to 50 per cent faster than unassisted animals. However, the drug only worked when applied before an advance in the light-dark cycle, equivalent to an east-bound flight.