Sleep wake profile and EEG spectral power in young or old senescence accelerated mice.
Changes occurring with age in cortical EEG and sleep-wake states architecture were examined in senescence accelerated prone (SAMP8) or senescence resistant (SAMR1) mice (age: 2 and 12 months) under baseline conditions or after a 4 h sleep deprivation (SD). In baseline conditions, an increase in slow wave sleep (SWS) amount (21-24%) occurs at the expense of the wakefulness (W) in old SAMP8 and SAMR1 mice versus young animals. In these conditions, SWS latency is reduced (67-72%). Moreover, in SAMP8 and SAMR1 mice, aging deteriorates paradoxical sleep (PS) architecture with more pronounced changes in SAMP8 (amount: -63%; episode duration: -44%; latency: +286%; circadian component loss; and EEG theta (theta) peak frequency (TPF): -1 Hz). During the 4 h recovery subsequent to a 4 h sleep deprivation, old SAMP8 mice exhibit an enhanced sensitivity resulting in SWS (+62%) and PS (+120%) rebounds, a characteristic of this inbred strain. Results obtained are discussed in line with the age-related learning and memory impairments existing in SAMP8 animals. In particular, the reduced cognitive performances described in old SAMP8 might be linked to the TPF deterioration during PS.
Colas
Damien
D
INSERM Unit 480, Claude Bernard University, 8 Avenue Rockefeller, 69373 Lyon Cedex 08, France.
Cespuglio
Raymond
R
Sarda
Nicole
N
D000367:Age Factors; D000375:Aging / Q000235:genetics / Q000502:physiology*; D000818:Animals; D001522:Behavior, Animal; D002940:Circadian Rhythm / Q000502:physiology; D003704:Dementia / Q000235:genetics / Q000503:physiopathology; D004195:Disease Models, Animal; D004569:Electroencephalography; D051379:Mice; D008815:Mice, Inbred Strains; D012890:Sleep / Q000502:physiology*; D020178:Sleep Disorders, Circadian Rhythm / Q000503:physiopathology; D013057:Spectrum Analysis / Q000379:methods; D014851:Wakefulness / Q000502:physiology*