Persistent ∆FosB expression limits recurrent seizure activity and provides neuroprotection in the dentate gyrus of APP mice.

Recurrent seizures lead to accumulation of the activity-dependent transcription factor ∆FosB in hippocampal dentate granule cells in both mouse models of epilepsy and mouse models of Alzheimer's disease (AD), which is also associated with increased incidence of seizures. In patients with AD and related mouse models, the degree of ∆FosB accumulation corresponds with increasing severity of cognitive deficits. We previously found that ∆FosB impairs spatial memory in mice by epigenetically regulating expression of target genes such as calbindin that are involved in synaptic plasticity.

Identification of the sleep-wake states in rats using the high-frequency activity of the electroencephalogram.

The electroencephalographic signal constitutes the main sign classically used for the identification of states of alertness. However, activities in the high frequency (>100 Hz) range have not been properly studied despite their high potential for sleep scoring in rodents. In the present study, we designed a method for the identification of the sleep-wake states in rats by exclusively using high-frequency activities of the electroencephalogram.

Temporal dynamics of the transition period between nonrapid eye movement and rapid eye movement sleep in the rat.

Study Objectives: We studied the sequence of events that occur in electroencephalogram (EEG), electromyogram (EMG), and ocular activities along the transition period between nonrapid eye movement and rapid eye movement (REM) sleep and their temporal relationships.

Methods: Twenty adult Wistar rats underwent polygraphic recordings of EEG, EMG, and eye movements during the transition periods. The studied EEG variables included the time of occurrence of the last sleep spindle and the evolution of the amplitudes of δ (1-5 Hz), θ (6-9 Hz), and high-frequency (110-160 Hz) oscillations (HFO).