碱烧伤大鼠角膜新生血管模型的初步探索

目的:探索相对稳定可靠的碱烧伤大鼠角膜新生血管(CNV)动物模型。方法:随机将48只S-D大鼠分成4组,每组12只,采用浸润1mol/L氢氧化钠的3mm滤纸片,分别制作烧灼时间为15、30、40、60s的碱烧伤鼠眼模型,每天裂隙灯观察角膜新生血管、角膜溃疡及前房积血情况,并在3、7、14、21、28d记录上述指标。结果:伤后3d,新生血管开始侵入角膜;7d,新生血管生长活跃,向中央烧灼区侵入;14d,新生血管达到生长高峰;14d后新生血管逐渐回退。烧伤后7d,15、30、40和60s组CNV诱导率分别为16.7%、75%、100%、100%,各实验组角膜新生血管诱导率随着烧伤时间延长而增加。。15sCNV散在稀疏分布,长度较短。30s组CNV接近烧灼区边缘,分布局限。40s组CNV致密,连接成网状,生长均匀一致。30s组和40s组间CNV长度和面积差异均具有统计学差异(P<0.05)。40s组前房积血率16.7%,表现为虹膜血管点片状渗血;60s组前房积血率83.3%,积血量多严重影响到角膜新生血管观察,两组前房积血发生率具有统计学差异(P<0.05)。60s组角膜溃疡率50%,穿孔率33.3%。结论:采用浸润1mol/L氢氧化钠溶液的3mm滤纸片烧灼中央角膜40s的大鼠模型是研究化学性角膜新生血管较理想的动物模型。

Study on the Rat Models of Corneal Neovascularization Induced by Alkali Burn

PURPOSE: The aim of this series of experiments was to test appropriate rat models of corneal neovascularization (CNV) induced by alkali injury. METHODS: All animals (n=48) were randomly assigned to four groups, each consisting of twelve eyes. Alkali injury was induced on day 0 by application of iN NaOH to right eyes of S-D rats for 15 30 AG and 6Os respectively. Biomicroscopic features including corneal neovascularization, corneal ulceration and hyphema were observed for 28 days. RESULTS: Corneal neovascularization began to invade pericornea on day 3 and flourished on day 7, then reached its developmental peak on day 14, and regressed gradually after day 14. The induced rate of CNV for groups 15s, 30s, 40, 60s, were 16.7%, 75%, 100%, 100% respectively, the induced rate of corneal neovascularization in all groups increased with time prolonging. CNV distributed sparsely in group iSs and its length was more shorter. CNV in group 30s reached the margin of burn area and distributed sparsely. There had uniform growth of CNV in group 40s and the hyphema was not more excessive than that of group 60s which was difficult to observe CNV. Significant difference (P < 0.05) was found between Group 30s and 40s in length and area of CNV respectively. The rate of hyphema was 16.7%, 83.3% respectively between Group 40s and 60s and significant difference (P < 0.05) was also found. The rate of corneal ulceration and perforation was 50% and 33.3% respectively in Group 60s. CONCLUSIONS: The appropriate induced time for S-D rat models of corneal neovascularization by using filter paper which diameter is 3 mm and inmerged solution of 1 mol/L sodium hydroxide was 40s. It's an ideal animal model for CNV induced by chemical injuries.