Expression Changes Of CXCR3 And CCR5 In Rat Retinas After Optic Nerve Injury

[Objective] We establish SD rats optic nerve clip injury model, research of the expression change of chemokine receptor CXCR3 and CCR5 in rat retinal of the different time points after optic nerve injury. To discuss the effects of CXCR3 and CCR5 to apoptosis of retinal ganglion cells after optic nerve injury. In order to further understand the mechanism of secondary retinal ganglion cell apoptosis after traumatic optic neuropathy to provides new train of thought.[Methods] One hundred and twenty adult SPF healthy female SD rats, and normal eyes. Rats were randomly grouped, divided into the optic nerve injury group (n=60), false optic nerve injury group (n=60), under the same conditions. Two groups at different time points after optic nerve injury is divided into five subgroups, which damage after 12 h,24 h group, and 3 d,5 d,7 d group. Injury group of left eye to eye injury in rats, using reverse holding forceps clamping force of 50 g 2 mm after the ball, clamping 10 s optic nerve, optic nerve injury model is set up; Fake injury group is set to false injury rats left eye, only expose the optic nerve, without clamping. To gather the eyeball of corresponding time points after injury. With FITC-lectin tag retinal microglial cells, GFAP tag retinal astrocytes, observed in the rat retina after optic nerve injury distribution of microglia and astrocytes and activation. By immunohistochemical technology at the same time, the detection of CXCR3, CCR5 at different time points after optic nerve injury in rats retina protein localization. The Real-Time PCR and Western Blot method in rats was detected in the different Time points after optic nerve injury of CXCR3 in the retinal tissue, CCR5 mRNA and the change of protein content. All results were analysised by the SPSS 17.0 statistical software.[Results] 1. FITC-lectin labeled microglia found sham group retina lectin-positive cells are mainly located in the retinal nerve fiber layer, inner plexiform layer, a small amount at the outer plexiform layer, the core layer and the outer nuclear layer of the distribution of small, and there was resting state. After the optic nerve injury 3d observed a small amount of the active state of microglia. The lectin-positive cells increased significantly after optic nerve injury 5d retinal layers appear, showing the active state.2. GFAP labeled astrocytes sham group found a small amount of GFAP expression retina only see in the retinal nerve fiber layer. GFAP expression after optic nerve crush injury with the extension of time gradually increased enhancement.5d after optic nerve injury in the retinal ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer appear GFAP expression was significantly increased, and extending outwardly visible linear expression.3. CXCR3, CCR5 immunohistochemical results:the sham group, only the retinal ganglion cell layer of the retina was found scattered in a very small amount has CXCR3/CCR5-positive cells. The retina after optic nerve injury began coloring the cells increased significantly.5d after optic nerve injury in retinal ganglion cell layer, inner nuclear layer, outer nuclear layer of positive staining cells increased significantly.4. Real-Time PCR method in the different Time points after optic nerve injury retina CXCR3, CCR5 mRNA expression level change found that 24 h after injury, CXCR3 mRNA expression is increased (P<0.05), and CCR5 mRNA expression also increases, but no statistical differences compared with false injury group (P>0.05); 3 d after injury, CXCR3 and mRNA expression of CCR5 quantity are greatly reduced, below the normal level, compared with false eye injury was statistically difference (P<0.05).5 d after injury, CXCR3, CCR5 mRNA expression was significantly increased to peak (P<0.05); 7 d after injury, CXCR3 mRNA expression is 5 d fell slightly after injury, compared with false eye injury is still statistically significant (P<0.05), and CCR5 mRNA expression basic back to normal levels, compared with false damage eyes no statistical difference (P>0.05).5. Western Blot method in the different time points after optic nerve injury retina CXCR3 and CCR5 protein expression level, results are basically consistent with rt-pcr detection:3 d after injury, CXCR3 and protein expression of CCR5 quantity are reduced to below the normal level, compared with false eye injury was statistically difference (P<0.05); 5 d after injury, CXCR3, CCR5 protein expression significantly increased to peak (P<0.05); 7 d after injury, CXCR3 protein expression level declined slightly, and back to normal CCR5 protein expression levels (P>0.05).[Conclusion] Microglia and astrocytes appears hyperplasia and activation in rat retina after optic nerve injury. After optic nerve injury, in the rat retina CXCR3 and CCR5 expression elevated point in time consistent with the retinal microglia and astrocyte activation unanimous lot of time, both of which may be associated with increased expression of glial activation after optic nerve contusion, may be involved and to increase the retina ganglion cell apoptosis.