牛磺酸对高原缺氧大鼠视网膜形态结构及SDH、LDH活性的影响

Effects of taurine on high-altitude hypoxia induced changes of retina morphology and SDH,LDH activity

目的观察急性持续性高原缺氧条件下视网膜结构、功能变化,探讨牛磺酸对视网膜缺氧损伤的保护作用。方法以低压舱模拟4 500 m和5 500 m高原条件,SD大鼠经2.4%牛磺酸干预后入舱缺氧。光镜观察视网膜层状结构,检测琥珀酸脱氢酶(SDH)和乳酸脱氢酶(LDH)活性的变化,电镜技术观察视网膜Müller细胞的超微结构。结果缺氧使内核层、内网状层和节细胞层受损。缺氧早期内网状层细胞移行高于对照组(P<0.05),4 500 m时牛磺酸促进细胞的移行,5 500 m早期抑制细胞移行。缺氧后Müller细胞肿胀,核崩解,细胞器变形,添加牛磺酸损伤减轻。缺氧导致SDH与LDH活性显著下降(P<0.05),牛磺酸能上调其活性(P<0.05)。结论缺氧引起视网膜内层细胞出现损伤,牛磺酸能显著提高SDH、LDH的活性,减轻视网膜的缺氧损伤,其保护作用与Müller细胞的功能和结构维持相关。

Objective To investigate retina structure and function under the condition of acute continuous hypoxia at high altitude and study on the protective effects of taurine on retina injury. Methods Low-pressure chamber was used to simulate 4 500 m and 5 500 m altitude. A total of 126 SD rats were used in this study, half assigned to the conditions under plain, 4 500 m and 5 500 m, the other half before the same assignment fed with 2.4% taurine in plain for a week. At 2, 6, 12, 24, 48, 72 h after entering the chamber, the eyes of SD rats were taken out, fixed and sectioned. Retina layer structure and uhrastructure of retina MOiler ceils were ob- served by light microscope and transmission electron microscope. The activity of succinate dehydrogenase （SDH） and lactate dehydrogenase （LDH） were detected with enzymohistochemistry. Results INL, IPL and GCL were injured in low oxygen. In the early period, migrating IPL ceils increased （ P 〈 0. 05 ）, and taurine increased migration at 4 500 m, but inhibited migration at 5 500 m. In hypoxia group Moiler ceils were swollen with nucleus degradation, organells swelling or deformation. Ceils in INL of taurine group had lower injury. Taurine up-regulated the activity of SDH and LDH （ P 〈 0.05 ） that decreased after hypoxia （ P 〈 0.05 ）. Conclusion Hypoxia results in the injury of retina inner layer ceils. Taurine can up-regulate the activity of SDH and LDH and relieve the injury. The protective effects are related to the function and structure of retina Müller cells.