兔急性高眼压视网膜四种氨基酸含量的动态变化

目的
测定家兔实验性急性高眼压模型视网膜谷氨酸（glutamate，GLU）、天门冬氨酸（aspartate，ASP）、γ-氨基丁酸（γ-aminobutyric acid，GABA）和甘氨酸（glycine，GLY）含量的动态变化。
方法
40只家兔分为8组，每组5只兔，每兔随机选一只眼作为实验眼。1～6组为实验组，实验眼在120 mm Hg（1 mm Hg=0.133 kPa）高压前房灌注持续15、30、45 min和高压灌注持续45 min后恢复正常眼压15、30、45 min时摘除眼球。实验对照组仅作前房穿刺后即摘除眼球。空白对照组直接处死动物摘除眼球。利用邻苯二甲醛柱前衍生法，高效液相色谱仪测定各组兔眼视网膜氨基酸的含量。
结果
高眼压灌注持续15 min组，视网膜GLU水平较实验对照组显著升高（t=5.9814，P=0.0003）；恢复正常眼压15min组，GLU含量再次显著升高，与实验对照眼比较差异显著（t=2.5970，P=0.0318）。ASP、GABA和GLY在实验过程中未发现有统计意义的变化。前房穿刺实验对照组与空白对照组的GLU含量比较无差别。
结论
急性高眼压早期以及恢复正常眼压早期均可导致视网膜GLU含量显著升高。
(中华眼底病杂志, 2002, 18: 146-148)

The variation of four amino acids release of the retina in acute ocular hypertension in rabbits

Objective To monitor the release of amino acids of the whole retina during and after experimental glaucoma by increasing the intraocular pressure （IOP）． Methods Experimental glaucoma was induced in one of the two eyes of rabbits by increasing IOP at 120 mm Hg for 45 min under infusion of saline in anterior chamber；then the pressure was released and the needle inserted into the anterior chamber was removed，this state was maintained for another 45 min．Every 15 min during the experiment 5 rabbits were killed and experimental eyes were enucleated．Aliquots（20 μl）of the retinal extracts（see below）were mixed with ophthaldialdehyde reagent and analysed for amino acid content by the HPLC method of Wangwei，using a 150 mm×4.6 mm,5 μm C18 column． Results A large increase in the release of glutamate，but not of the other three amino acids monitored，occurred during initial experimental ocular hypertension．It reached peak value of（111.73±17.46）10-5 mmol/g at 15 min of hypertension．15 min after release of intraocular pressure，again，immediately large and specific increase in the concentration of glutamate was reached to（102.96±51.91）10-5 mmol/g．In eyes subjected to paracentesis of anterior chamber，no difference was found between experimental eyes and controls. Conclusion These results suggest that glutamate is triggered by increasing the IOP，and it releases not only during the period of experimental ocular hypertension，but also afterwards. (Chin J Ocul Fundus Dis, 2002, 18: 146-148)