Experimental Study Of Chondroitinase ABC Promotes Functional Recovery After Spinal Cord Injury Of Rat

Objective: Intrathecal treatment with chondroitinase ABC degraded CS-GAG at the injury site,upregulated a regeneration-associated protein in injuried neurons, promoted regeneration of both axons,and promoted functional recovery of locomotor and proprioceotive behaviours.Our results demonstrate that CSPGs are important inhibitory molecules in vivo and suggest that their manipulation will be useful for treatment of human spinal injuries.Method: Firstly,make the transverse injury model on adult SD female rats T_7.8 dorsal column,concurrently,a silastic tube was inserted intrathecally to lie just rostral to the lesion site.In experimental group (n=20) ,μlhigh-purity,protease-free chondroitinase ABC was injected on alternate days for 10 days after lesion;In control group (n=20) ,6μl sodium chloride was injected. Secondly,Rats were perfused at 2 weeks after lesion to check effectiveness of treatment in removing CSPGs with OBT1696,tested behaviourally over 10 weeks ( first,second,third,fourth,fifh,sixth,eightfh,and tenth week ) ,then perfused at 10 weeks after lesion for analysis of CST regeneration and astrocytes inhibition with NF-200,GFAP,NSE,PKC-γ,the positive expression are analysis quantitatively with a computer image analysis system,and the results are analyzed respectively by one-way ANOVA. Reresults:l.The mean score of behavioral evaluation of hindlimbs is 53.5 in the normal group.there is no differentiation between the treatment group and the vehicle infused group after 3W.there is an apparent increase of scores in the treatment group compared with the vehicle group after 4W (P<0.05).2. OBT1696: Compared with the treatment group and the vehicle infused group, OBT1696 expression in the vehicle infused group increase significantly than the treatment group (P<0.05).NF-200:NF-200 expression in the treatment group increase significantly than the vehicle infused group(P<0.05). GFAP:GFAP expression in the vehicle infused group increase significantly than the treatment group (P<0.05).NSE:NSE expression in the vehicle infused group increase significantly than the treatment group (P<0.05). PKC-γ: The activity of PKC-γin cell membrane increased in the vehicle infused group than the treatment group.Conclusions: 1.CSPGs are important inhibitors in extracellular matrix,and inhibit regeneration of axons by some ways.2.ChABC degraded CSPGs at the injury site,and promoted regeneration of spinal cord and functional recovery of locomotor and proprioceptive behaviours.