Notch1 knockdown disturbed neural oscillations in the hippocampus of C57BL mice

Neural oscillations and their interactions are associated with the coordination of neural groups, which provide a mechanism underlying information processing of brain functions. Notch1 receptor is involved in the neurological and psychiatric disorders, such as neurodevelopmental deficits, cerebral ischemia, Alzheimer's disease and depression. Here, we investigated the dynamics of neural oscillations in hippocampus of Notch1^+/- mice in urethane-anesthetized state. Notch1 knockdown altered the distribution of power in the hippocampal DG areas, reduced theta (3-8 Hz) power and enhanced low gamma (LG, 30-50 Hz) and high gamma (HG, 50-100 Hz) power. Moreover, theta-gamma phase-amplitude coupling in the hippocampal DG area was markedly impaired in the Notch1^+/- mice. The data further showed that the expression of NR2B was decreased, and the expressions of GABAAR_α1, GAD67 and parvalbumin were considerably increased after Notch1 knockdown. Taken together, our results suggest that Notch1 genetic deficiency significantly impaired the corss-frequency coupling of neural oscillations, and their interactions in the hippocampal DG region by means of disrupting the balance of excitatory and inhibitory receptors, which could be an underlying mechanism of cognitive impairment in neuropsychiatric disorders.