Fig. 2

Hippocampal GPR17 knockdown prevents LPS-induced cognitive impairment in mice. A Experimental procedure for the test schedule. LV-EGFP or LV-GPR17–shRNA–EGFP were microinfused into bilateral DG regions of the hippocampus of mice, followed by LPS (0.25 mg/kg, i.p.) or its vehicle was administered 7 days after the viral infusions 3 weeks, and then, the OFT, MWM, and NORT tests were conducted in mice. B Imaging of green fluorescent protein expression in the hippocampus after 4 weeks of viral vector injection. Scale bar = 100 μm. C Representative immunoreactive bands of GPR17 protein in the hippocampus. β-Actin was used as an internal control, and relative protein levels were quantified by densitometry analysis using Image J software. Quantification of GPR17 protein (D) and mRNA (E) levels in the hippocampus was shown, n = 4 mice/group. Scale bar, 100 μm. F Schematic diagram of experimental apparatus and the heat map of mouse movement in the OFT. G Total distance in the OFT. H Representative trajectories of mice from each experimental group in the probe trial. I During the 2-day visible platform test, there were no differences in the escape latency among all groups in the MWM test. Escape latency was changed on the hidden platform during the 3-day acquisition trials. J Time spent in the target quadrant during the probe trial test. K Number of platform crossings during the probe trial test. L Swimming speed among all groups during probe testing on day 6. M Schematic diagram of experimental apparatus of the NORT. N Discrimination index of the NORT. Values shown are expressed as mean ± SEM; n = 12 mice/group. *P < 0.05, **P < 0.01 versus Veh + LPS