Abstract: Objective To explore the effect of Cx43 protein on improvement of learning and memory ability induced by enriched environment (EE) in rats with traumatic brain injury (TBI). Methods TBI model was made by fluid percussion injury (FPI) in Sprague-Dawley rats. The TBI rats were divided into EE group (A), standard housing (ST) group (B), Cx43 specific antisense oligonucleotides (Cx43 ASODN)+EE group (C) and scrambled sequence ODN+EE group (D) with 6 rats in each group. Another 6 normal rats were taken as the control group. Groups C and D were given hippocampal microinjection of Cx43-ASODN (2 μl/d/rat, 1.5 mmol/L) and ScrbASODN (2 μl/d/ rat, 1.5 mmol/L) respectively. Morris water maze was used to evaluated the learning and memory ability. Results The latency was longer and the traversing times was less in group B than in the control group (P<0.05). The latency was shorter in group A than in group B (P<0.05), and there was no significant difference between group A and the control group (P>0.05) from the 9th day after injury. The traversing times was more in group A than in group B and there was no significant difference between group A and the control group (P>0.05). The latency was longer and the traversing times was less in group C than in group A (P<0.05). Conclusion Cx43 protein may participate in the improvement of the learning and memory ability induced by EE in rats with TBI.

Key words: traumatic brain injury, Cx43 protein, learning and memory ability, enriched environment, rats