摘要背景 选择性激光小梁成形术(SLT)可增加前房水排出,降低开角型青光眼患者的眼压,但其作用机制尚不清楚.小梁网房水排出阻力受到细胞外基质(ECM)影响,基质金属蛋白酶3(MMP-3)、MMP-9与小梁网ECM的降解密切相关. 目的 利用永生化小梁细胞建立SLT激光效应模型,观察激光效应对小梁细胞表达MMP-3及MMP-9的影响.方法 将永生化人小梁细胞与色素颗粒混悬液共同隔夜培养16h,用SLT所用的Q开关倍频532 nm Nd:YAG激光照射人小梁细胞,制备SLT激光效应细胞模型,激光能量为0.2mJ,光斑直径为400 μm,脉冲持续时间为3 ns.分别于激光照射后1、4、8、12和24 h,采用实时荧光定量PCR法检测激光照射前后小梁细胞中MMP-3 mRNA及MMP-9 mRNA的相对表达情况;ELISA法检测激光照射前后不同时间点培养液中MMP-3及MMP-9蛋白质量浓度的变化. 结果 SLT激光照射人小梁细胞前及照射后1、4、8、12和24 h后细胞中MMP-3 mRNA的相对表达量分别为1.00、1.32±0.12、2.08±0.05、2.34±0.04、2.77±0.05、2.49±0.27,各组间差异有统计学意义(F=15.966,P=0.007),其中激光照射后各时间点细胞中MMP-3mRNA的相对表达量均明显高于对照组,至12h表达量最高,差异均有统计学意义(均P＜0.05).激光照射前后不同时间点细胞中MMP-9 mRNA的相对表达量分别为1.00、0.91±0.10、1.27±0.07、1.46±0.07、1.69±0.09、0.87±0.09,各组间差异有统计学意义(F=30.526,P=0.005),其中激光照射后4、8和12h小梁细胞中MMP-9 mRNA的相对表达量明显高于对照组,差异均有统计学意义(P=0.001、＜0.001、＜0.001).激光作用后不同时间点小梁细胞培养液中MMP-3及MMP-9蛋白的质量浓度均明显高于相应时间点对照组的检测值,差异均有统计学意义(均P＜0.05). 结论 SLT激光效应小梁细胞模型在激光作用后早期对MMP-3及MMP-9基因的表达和分泌均明显增加,但其表达随着激光照射后时间的延长而减弱.

abstractsBackground Selective laser trabeculoplasty (SLT) can increase the outflow of aqueous humor and reduce the intraocular pressure of patients with open angle glaucoma,but its mechanism is unknown.To investigate the mechanism of SLT would improve the therapeutic effect of SLT.The aqueous outflow resistance in trabecular meshwork was affected by the extracellular matrix (ECM).Matrix metalloproteinase-3 (MMP-3) and MMP-9 were closely related to ECM degradation in trabecular meshwork.Objective This study was to observe the effects of SLT on the expressions MMP-3 and-9 in human trabecular ceils in vitro.Methods Immortallized human trabecular cells were cultured with pigment particles mixed suspension for 16 hours and incubated overnight.Then the cells were irradiated with Q switch frequency doubling 532 nm Nd:YAG laser to establish SLT-effective cells with the energy of 0.2 mJ,spot diameter of 400 μm and pulse duration of 3 ns.The expressions of MMP-3 mRNA and MMP-9 mRNA in the cells were detected by fluorescence quantitative real time PCR before and 1 hour and 4,8,12,28 hours after exposure of laser.The concentrations of MMP-3 and MMP-9 in the medium were assayed using ELISA 1 hour and 4,8,12,28 hours after exposure of laser and compared between the non-irradiation group and the irradiation group.Results The relative expressing levels of MMP-3 mRNA were 1.00,1.32±0.12,2.08±0.05,2.34±0.04,2.77± 0.05 and 2.49±0.27 in the non-irradiation group and irradiation for 1 hour and 4,8,12,28 hours after exposure of laser SLT,showing a significant difference among the groups (F =15.966,P=0.007),and relative expressing levels of MMP-3 mRNA were significantly higher in various time points after laser irradiation than those of the non-irradiation group (all at P＜0.05).The relative expressing levels of MMP-9 mRNA were 1.00,0.91 ±0.10,1.27 ± 0.07,1.46±0.07,1.69±0.09 and 0.87±0.09 in the non-irradiation group and irradiation for 1 hour and 4,8,12,28 hours after exposure of SLT,which was considerably different among the groups (F =30.526,P =0.005),and significant increased values were seen in the 4,8 and 12 hours after irradiation compared with the non-irradiation group (all at P＜0.05),with highest expression in the irradiation for 12-hour group.The concentrations of MMP-3 and MMP-9 proteins in medium were significantly increased in various time points after laser exposure in comparison with the control group (all at P＜0.05).Conclusions The expressions of MMP-3 and MMP-9 in human trabercuolar cells upregulate and the secretion ability of human trabecular cells to MMP-3 and MMP-9 proteins improves in early stage of SLT in vitro.However,these procedures gradually diminish with the lapse of time.