Viagra helps hamsters overcome jet lag

A hamster-size dose of sildenafil, more commonly known by its marketing name Viagra, helps the rodent recover more quickly from a six-hour advance in its daily cycle, researchers report.

Originally developed for the treatment of high blood pressure and angina, Sildenafil works by interfering with an enzyme that reduces levels of a naturally-occurring compound, cyclic guanine monophosphate (cGMP). In the brain, cGMP has an important function in a signalling pathway that regulates the body’s daily clock.

Biotechnologist Patricia Agostino and colleagues at the Universidad Nacional de Quilmes in Argentina injected hamsters with sildenafil at night, before turning on bright lights six hours earlier than natural sunrise. The team then observed how the hamsters adjusted to the change, by noting how soon they began running in their exercise wheels.

Sildenafil-boosted hamsters recovered from the jet lag up to 50 percent more quickly than unassisted animals. However, the drug only worked when applied before an advance in the light/dark cycle, equivalent to an eastbound flight, rather than the reverse.

The scientists believe that frequent flyers and shift workers could benefit from moderate doses of sildenafil.

The study will be published in the U.S. journal, PNAS, this week.