Fig. 10

Euthyroid HT increases frontal lobe microglial attachment to neurons and decreases presynaptic terminals covering neurons. a Representative images of Ibal-labeled microglia and hematoxylin-stained neurons in mice (n = 5/group). Magnified images of the boxed areas are shown. b Neuronal quantification. (c Number of microglia-neuronal overlaps. d Representative EM images of microglia-neuron interactions, indicating an abnormal apposition of microglia with neurons in euthyroid HT mice using EM that was not quantified. Surface areas of neurons (green) of HT mice occupied by microglia (red) were bare of synaptic endings (yellow), whilst neurons (green) juxtaposed with microglia (red) in controls had abundant synaptic contacts (yellow). e EM images of presynaptic terminals (yellow) covering neurons. f % of the neuronal cell surface covered by presynaptic terminals (yellow) (n = 4 mice /group). Data are the mean ± SEM; Scale bars: a = 20 μm; d = 2 μm; e = 1 μm