Figure 2. Down-regulation of circLrp1b in rat brain enhances the effects of dexmedetomidine in neurological outcome after traumatic brain injury. Rats were administered an intracerebroventricular injection of sh-circLrp1b before TBI induction, followed by intraperitoneal injection of 20 μg/kg dexmedetomidine (DEX). (A) Representative track plots of animal paths in the place navigation task and spatial probe task of the Morris water maze test in rats from different groups (left panel) and quantification of the latency time and the number of the crossing were recorded (right panel). (B) Application of the modified Neurological Severity Score (mNSS). (C) Calculation of the brain water content, as is described in the Materials and Methods section. (D) Expression levels of circLrp1b, miR-27a-3p, and Dram2, as determined using real-time quantitative reverse transcriptase polymerase chain reaction (qRT-PCR). Each experiment was repeated 6 times. ***p < 0.001, compared with Sham; ##p < 0.01, ###p < 0.001, compared with TBI + NC; &p < 0.05, compared with TBI + sh-circLrp1b. Representative 400× images of the hematoxylin and eosin (H&E)-stained (E) and Nissl-stained (F) hippocampal sections from the experimental groups. Scale bar: 50 μm.