Figure 6. miR-195 knockdown produces learning and memory deficits in rats. A, Verification of the injection sites by Evans blue staining in stereotaxic surgery. B, Quantification of miR-195 in the hippocampus and the cortex tissues after stereotaxic injection for 8 weeks using qRT-PCR. Rats were transfected with lenti-pre-AMO-miR-195, lenti-pre-AMO-miR-195 + lenti-pre-miR-195, or NC. Data shown were from six rats for each group. *p < 0.05 versus NC; #p < 0.05 versus lenti-pre-AMO-miR-195. C, Average escape latency to platform at day 1 after lenti-pre-AMO-miR-195, lenti-pre-AMO-miR-195 + lenti-pre-miR-195 treatment, and NC. n = 6 for NC group, n = 8 for lenti-pre-AMO-miR-195 group, and blank n = 8 for lenti-pre-AMO-miR-195 + lenti-pre-miR-195 group. D, Mean daily latencies to escape from the start point onto the hidden platform after lenti-pre-AMO-miR-195, lenti-pre-AMO-miR-195 + lenti-pre-miR-195 treatment for 8 weeks. n = 6 for NC group, n = 8 for lenti-pre-AMO-miR-195 group, and n = 8 for lenti-pre-AMO-miR-195 + lenti-pre-miR-195 group. E, Number of times crossed the target platform location during probe trial. *p < 0.05 versus NC, n = 6. F, Percentage of swimming distance in the target quadrant relative to the total distance of the pool during probe trial. *p < 0.05 versus NC, #p < 0.05 versus lenti-pre-AMO-miR-195, n = 6. G, Representative path tracings of the probe test on day 6 in the MWM test for each group. H, I, APP (H) and BACE1 (I) protein levels in the hippocampus and the cortex tissues after treatment by lenti-pre-AMO-miR-195 and lenti-pre-AMO-miR-195 + lenti-pre-miR-195 for 8 weeks. *p < 0.05 versus NC, #p < 0.05 versus lenti-pre-AMO-miR-195, n = 6. J, Aβ42 levels in the hippocampus tissues from lenti-pre-AMO-miR-195 and lenti-pre-AMO-miR-195 + lenti-pre-miR-195 treatment for 8 weeks and from NC rats, measured by ELISA assay. *p < 0.05 versus NC, #p < 0.05 versus lenti-pre-AMO-miR-195, n = 5. K, Elevated Aβ42 levels in plasma of rats treated by lenti-pre-AMO-miR-195 detected by ELISA assay. *p < 0.05 versus NC, #p < 0.05 versus lenti-pre-AMO-miR-195, n = 5. L, M, The ratios of Aβ42/Aβ40 in the hippocampus tissues (L) and plasma (M) from lenti-pre-AMO-miR-195 and lenti-pre-AMO-miR-195 + lenti-pre-miR-195 treatment for 8 weeks and NC rats by ELISA assay, *p < 0.05 versus NC, #p < 0.05 versus lento-pre-AMO-miR-195, n = 5.