A Consensus Definition of Cataplexy in Mouse Models of Narcolepsy
|Title||A Consensus Definition of Cataplexy in Mouse Models of Narcolepsy|
|Publication Type||Journal Article|
|Year of Publication||2008|
|Authors||Scammell, TE, Willie JT, Guilleminault C, Siegel JM|
|Keywords||atonia, Hypocretin, orexin, paralysis, positive affect, REM sleep|
People with narcolepsy often have episodes of cataplexy, brief periods of muscle weakness triggered by strong emotions. Many researchers are now studying mouse models of narcolepsy, but definitions of cat- aplexy-like behavior in mice differ across labs. To establish a common language, the International Working Group on Rodent Models of Nar- colepsy reviewed the literature on cataplexy in people with narcolepsy and in dog and mouse models of narcolepsy and then developed a con- sensus definition of murine cataplexy. The group concluded that murine cataplexy is an abrupt episode of nuchal atonia lasting at least 10 sec- onds. In addition, theta activity dominates the EEG during the episode, and video recordings document immobility. To distinguish a cataplexy episode from REM sleep after a brief awakening, at least 40 seconds of wakefulness must precede the episode. Bouts of cataplexy fitting this definition are common in mice with disrupted orexin/hypocretin signal- ing, but these events almost never occur in wild type mice. It remains unclear whether murine cataplexy is triggered by strong emotions or whether mice remain conscious during the episodes as in people with narcolepsy. This working definition provides helpful insights into mu- rine cataplexy and should allow objective and accurate comparisons of cataplexy in future studies using mouse models of narcolepsy.
|Short Title||Cataplexy in Murine Narcolepsy|