The Study On The Intracellular Expression Of LOX After Acute Spinal Cord Injury In Rats

Objectives The aim of this study was using improved Allen impact device, to investigating the expression of LOX during the recovery phase after acute spinal cord injure.Methods 1)Adult female Sprague-Dawley rats were randomly divided into A、B、C 3groups, 4 rats in each group: group A 25 g.cm(10g×2.5cm),group B 35 g.cm(10g×3.5cm)、group C 45 g.cm(10g×2.5cm)potential energy hitting spinal cord. 2)48 adult female Sprague-Dawley rats were randomly divided into A,B,C,D 4 groups, group A was β-Aminopropionitrile, BAPN, inhibitor of LOX, group B was Co Cl2, promoter of LOX,group C was A positive injury, group D was sham. After replicates acute spinal cord injury model by method of improved Allen impact device,harvesting spinal cord tissue and making paraffin block in different points after injury(1,3,7,14and30d),and performing IHC.Results 1)Acute spinal cord injury model replicated by 25 g.cm potential energy.2)LOX were expression in cytoplasm of normal spinal cord and injury spinal cord.Positive color were brown particle and small pieces diffusivity in section. There are several kinds of form, such as rounded,oval,triangular and so on. 3)The positive area percentage of LOX in different spinal cord injury groups were group A30.03%、group B73.96%,group C 42.35%,group D 5.54%, the difference were significant(P<0.05).There were very few positive LOX expression in normal spinal cord. The tendency of LOX expression changing in group A,B,C was similar. Increasing started at day 1,reaching peak level at day 3, decreasing started at day 7. Comparing A,B,C groups with group D,the difference were all significant(P<0.05). Control group A was lowest. The other groups’ Bax level higher than group A, and this kind of increasing was most obvious in group C. Comparing with group C, the expression of Bax in group D decrease and significant(P<0.05).Conclusions 1)The method of improved Allen impact device can reproduced acute spinal cord injury model successfully.Another important point was it can avoid the accident induced by rats moving. 2)There were very few positive LOX expression in normal spinal cord. 1 day after SCI the expression of LOX increased significantly. BAPN can decreasing LOX expression by inhibiting the Covalent cross-linking between the collagen and elastin formation, Co Cl2 can decreased LOX expression by exacerbating anoxia. 3) LOX expressed in neurocyte inactivated, when the level of substrate increased,LOX will increase. And the increase of LOX can promote Covalent cross-linking between the collagen and elastin formation and ECM.