Lentivirus-mediated Rna Interference Inhibits Cdh1 Expression In The Recovery Of Spinal Cord Injury In Rats

AIM: To investigate the expression of Cdh1 in the sensorimotor cortical of rats after spinal cord injury and to study the repairing effect of changing the expression of Cdh1 by lentiviral-mediated RNAi.METHODS: Twenty male Sprague-Dawlcy rats were randomly divided into normal group and operation group which included 2 subgroups (1, 2 weeks). Rats models of spinal cord injury were implemented with Allen method after removing lamina of vertebral and spinous process of T10 and T11.Tl0 laminectomy was performed in the control group.Both groups of rats were killed respectively in lw, 2w. The mRNA of the sensorimotor cortex was extracted by Trizol method. The expression of Cdh1 was examined by quantitive real time PCR. The other thirty male Sprague-Dawlcy rats were randomly divided into saline injection group (Group A, n=10), lentivirus vector injection group (Group B, n=10) and recombinant lentiviral injection group (Group C, n=10). Five rats of every group were killed ten days after injection. The mRNA of the sensorimotor cortex was extracted by Trizol method and examined by quantitive real time PCR. At different times after injury, the behavior was evaluated with Basso-Beattie-Bresnahan (BBB). All groups received 10% biotinylated dextran amine (BDA) injections in the same region at 6 weeks after injury. Mice that received BDA were killed by anesthetic overdose at 8weeks after injury and perfused with 4% paraformaldehyde. Spinal cords were removed and sectioned serial fluorescence microscope.RESULTS: The expression of Cdh1 mRNA in operation group was significantly higher than those in normal group (P<0.05). The expression of Cdh1 mRNA in group C was lower than in group A or group B 10 days after injection(P<0.05). In addition,the BBB assessment in group C was higher than in group A or group B in 6 weeks after injury(P<0.05). A novel population of BDA-labeled axons could be observed extending past the lesion in group C, while only a few could be observed in group A and group B.CONCLUSION: The expression of Cdh1 mRNA is increased after spinal cord injury. Silencing of Cdh1 enhances the growth of the axonal fibers. APC-Cdh1 appears to play a role in inhibiting axonal growth.