Fig. 5

Physiological network oscillations are altered in the adult hippocampus in absence of GluK1 expression in the GABAergic neurons. A Image illustrating the localization of the fluorescently labelled recording electrode in a coronal section from the mouse hippocampus, in CA1 –DG (i) and CA3 (ii). The traces show an example of the LFP recording of oscillatory activity at different regions of the male control mouse hippocampus, and the heat map illustrates the color-coded voltage plots at identical time-scale after 350 Hz low pass filtering. B Oscillatory power in the theta (4–12 Hz) frequency range for channels located in the CA1 stratum moleculare (CA1 mol), CA1 stratum pyramidale (CA1 pyr) and dentate gyrus (DG), for male and female control and Gad-Grik1^−/− mice (n = 5 / group). C Oscillatory power in the gamma (20–90 Hz) frequency range, for the same recordings as in B. * p < 0.05, 2-way ANOVA, Tukey’s correction for multiple comparisons). D Oscillatory power in the gamma range, as function of the theta phase angle divided into 8 equal sized bins. The solid lines represent second order polynomial (quadratic) curve fit. Gamma power in the CA1 is more strongly modulated by theta phase (**** p < 0.0001, n = 5, quadratic regression, sum-of-squares F test) in male (i), but not in female (ii) (n = 5, quadratic regression, sum-of-squares F test) Gad-Grik1^−/− mice. E Rate of occurrence of ripple oscillations in the CA1 pyramidal layer. * p < 0.05, 2-way ANOVA. F Duration of ripple oscillations detected in the CA1 pyramidal layer. *p < 0.05, unpaired t-test. G Percentage of ripples lasting more than 100 ms. All data from idle or resting epochs, detected from videos recorded simultaneously with the electrophysiological recording. ** p < 0.005, unpaired t-test. Bars in all panels represent mean ± SEM