Drug offsets sleep deprivation effects, in monkeys

In an article in the research journal PLoS Biology, Dr. Sam A. Deadwyler and his associates propose that CX717 would particularly benefit individuals affected by extended work hours or night shifts.

To test this possibility, they taught monkeys to perform a "delayed-match-to-sample task," in which they were presented with a single image on a computer screen, then would use a cursor to identify that image in a group of several different images.

During normal alert conditions, performance accuracy of the animals was improved from an average of 75 percent to 90 percent after an injection of CX717. The drug also shortened response times, suggesting that "CX717 also facilitated attentional processes related to speed of responding on successful trials."

When the monkeys were subjected 30-36 hours of sleep deprivation, average performance accuracy dropped to 63 percent, which was restored to 84 percent after CX717 treatment.

The distinct shifts in EEG recordings and changes in brain scans following sleep deprivation were also reversed by drug treatment.

"The fact that (compounds like) CX717 can temporarily alleviate the effects of prolonged periods of sleep deprivation...indicates their potential applicability to many circumstances in which human performance is compromised by extensive sleep loss," Deadwyler and his associates suggest.

They add that these new agents may be preferable to psychostimulants, caffeine or the relatively new anti-sleepiness drug Provigil, because these "may be limited due to their potential for addiction and/or their potent stimulant actions, which can distort cognitive and sensory processes at doses required to counteract the effects of sleep deprivation."

SOURCE: PLoS Biology, September 2005.