Fig. 2

Synapse loss caused by excessive microglial phagocytosis in the hippocampus of mice after neonatal sevoflurane exposures. A Representative confocal images of IBA1⁺ microglia (red) containing PSD95⁺ puncta (green). Orthographic view and 3D rendering are shown. Scale bars = 5 μm. B Quantification analysis showed that the sevoflurane group had increased PSD95⁺ puncta in microglia. n = 20. Unpaired t-test. C Representative confocal images of GFAP⁺ astrocytes (red) containing PSD95⁺ puncta (green). Orthographic view and 3D rendering are shown. Scale bars = 5 μm. D Quantification analysis showed that the two groups had similar volumes of PSD95⁺ puncta in astrocytes. n = 20. Unpaired t-test. E Representative confocal images and 3D surface rendering of PSD95⁺ puncta (cyan) in CD68⁺ (green) positive microglia (red). Scale bars = 5 μm. F Representative confocal images of CD11b (green) and IBA1 (red) immunoreactivity. Scale bars = 20 μm. G Quantification analysis showed that the sevoflurane group had increased colocalization of CD11b and IBA1. n = 6. Unpaired t-test. H Representative confocal images of CD68 (green) and IBA1 (red) immunoreactivity. Scale bars = 20 μm. I Quantification analysis showed that the sevoflurane group had increased colocalization of CD68 and IBA1. n = 6. Unpaired t-test. J Representative confocal images and 3D surface rendering of IBA1⁺ microglia (red) containing PSD95⁺ puncta (green) in sevoflurane-treated mice receiving PBS or minocycline. Scale bars = 5 μm. K Quantification showed that minocycline led to a decrease in the engulfment index. n = 20. Unpaired t-test. L Representative confocal images of Vglut2 (green) and PSD95 (red) in sevoflurane-treated mice receiving PBS or minocycline. Scale bars = 5 μm. M Quantification of colocalization revealed that minocycline increased synapse density. n = 6. Unpaired t-test. Data are mean ± SEM. *P < 0.05, ** P < 0.01, *** P < 0.001