急性甲醇中毒大鼠模型及其眼部改变的研究

Rat Model of Acute Methanol Poisoning with Ocular Changes

【目的】探讨急性甲醇中毒大鼠模型的制作方法及其眼部改变,为研究中毒后视功能损害及救治方法建立基础。【方法】SD大鼠32只,随机分为A(低剂量甲醇组)、B(高剂量甲醇组)、C(生理盐水对照组)、D(空气对照组)4组,每组8只。A、B组吸入N2O/O2混合气及不同剂量甲醇灌胃,C组吸入N2O/O2混合气及生理盐水灌胃,D组置于正常空气中并按B组剂量给予甲醇灌胃,观察各组大鼠一般情况、体质量及眼部改变、静脉血甲醇浓度、视网膜电图和视网膜组织学改变。【结果】染毒大鼠反应迟钝、运动失调,视盘充血水肿、视网膜点状出血,A组大鼠体质量为(187±12)g,B组为(176±13)g,较C、D对照组显著减轻(P<0.05);A组视网膜电图a、b波振幅分别为(87±13)μV、(187±38)μV,B组a、b波振幅分别为(53±19)μV、(132±39)μV,与对照组相比明显下降(P<0.05);视网膜在光镜下表现为各层细胞水肿、排列紊乱及空泡化;电镜下细胞凋亡,线粒体肿胀、嵴断裂;B组动物上述改变尤其明显。【结论】吸入N2O/O2混合气及甲醇灌胃可建立急性甲醇中毒的大鼠模型,出现典型的视网膜结构和功能改变。

[Objective] To develop a rat model manifesting acute methanol poisoning and study the ocular changes so as to lay foundations for further investigation of visual impairment. [Methods] Thirty-two SD rats were randomly divided into group A （low methanol dosage group, n=8）, B （high methanol dosage group, n=8）, C （saline control group, n=8） and D （air control group, n=8）. Group A and B were exposed to a mixture of N2O/O2 and given different dosage of methanol by gavage. Group C was exposed to N2O/O2 and given the same volume of saline as group B. Group D was exposed to normal air and given the same dosage of methanol as group B. General condition, ocular changes, methanol concentration in venous blood, electroretinogram and retinal histopathologic changes were analyzed. [Results] Methanol-intoxicated rats were characteristic by slow reaction, incoordination, optic disc hyperemia and edema and retinal haemorrhage. Body mass loss was significant in group A and B when compared with group C and D （P〈 0.05）, which was （187±12） g in A and （176±13） g in B, respectively. A-wave and b-wave of electroretinogram were markedly reduced in group A and B （P〈 0.05）, which was （87±13） μV and （187±38） μV in group A, and （53±19） μV and （132±39） μV in group B, respectively. Retinal edema, derangement of cells and vacuoles were obvious under light microscope. Changes under electromicroscope were characteristic by cell apoptosis, mitochondria swollen, and cristae disruption. These changes were more obvious in group B. [Conclusion]Acute methanol poisoning in rats could be successfully duplicated by exposure to a mixture of N2O/O2 methanol administration by gavage, with typical retinal structural and functional changes.