Figure 8.

rdTBI caused spontaneous, unprovoked, recurrent seizures. a, Pie chart representing the incidence of seizures in mice with rdTBI. Four of 9 (44%) mice developed recurrent spontaneous seizures; 3 (33%) mice developed convulsive seizures; 1 (11%) mouse developed recurrent spontaneous nonconvulsive seizures; and 5 of 9 (56%) mice had no seizures. b, EEG trace of a 3xSham mouse 50 d after the electrode placement surgery. Channel (Ch) reading: right parietal electrode to left parietal electrode. c, EEG trace of a mouse with a spontaneous convulsive seizure 35 dpi. The enlarged panel (with time scale 3 s) indicates emergence of high-amplitude evolving repetitive spikes and spike-waves followed by postictal depression (right part of the enlarged panel). Channel reading as in b and d, EEG traces of a nonconvulsive seizure at 65 dpi consisting of repetitive high-amplitude spike-and-slow wave discharges in the absence of any movement of the mouse. Channel reading: Ch1 right frontal to left parietal electrode; Ch2 left parietal to right parietal electrode. e, EEG power spectrum analysis of normal EEGs and convulsive and nonconvulsive seizures. The power density spectra are color-coded on a logarithmic scale (dB). Pink panels in c–e show the location of the ictal event in the EEG and in the corresponding power spectrum. f, Seizure frequency in rdTBI mice with convulsive and nonconvulsive seizures compared with 3xSham. g, Histological confirmation of the absence of gross tissue loss induced by either rdTBI or electrode placement surgery. h, Diffuse loss of Glt1 and Kir4.1 expression in astrocytes in mice with spontaneous recurrent seizures and quantification of Glt1 loss in i. See Figure 8-1 for breakdown of sample sizes dependent on sex for representative images and detailed numerical data for all statistical group comparisons. *p ≤ 0.05, **p ≤ 0.01.