模拟海拔5000m高原间断性缺氧对大鼠视网膜的损伤及牛磺酸的防护作用

目的探讨间断性低氧对大鼠视网膜的损伤及牛磺酸的防护作用.方法动物经基础饲料饲养或牛磺酸干预4周后,利用低压舱模拟5 000 m海拔高度,每天低氧停留时间为8 h,连续3 d.用氨基酸分析仪检测视网膜中牛磺酸、谷氨酸和γ氨基丁酸的含量,通过免疫组织化学方法观察大鼠视网膜中谷氨酸和γ氨基丁酸的分布情况,通过电镜观察大鼠视网膜外网状层双极细胞超微结构变化.结果高原缺氧引起大鼠视网膜各层组织及细胞结构的明显损伤,而牛磺酸干预能减轻缺氧对视网膜的损伤.高原缺氧导致视网膜组织中的谷氨酸和牛磺酸含量显著增加,而牛磺酸干预能拮抗缺氧引起Glu的升高.结论牛磺酸营养干预能明显拮抗高原缺氧引起的视网膜组织中的谷氨酸含量增加而降低谷氨酸的兴奋毒性作用,从而对视网膜的神经元起到保护作用.

Protective effect of taurine on the damage of retina in rats exposed to 5 000 m high altitude

Objective To study the protective effect of taurine on the damage of retina in rats exposed to high altitude. Methods After taurine nutritional intervention for 4 weeks, rats were exposed to 5 000 m high altitude in a hypobaric chamber for 3 d (8 h/d). The concentrations of taurine, glutamate, and gamma-aminobutyric acid in rat retina were determined with the amino acid analyzer. The distribution of glutamate and gamma-aminobutyric acid in rat retina was determined by immunohistochemistry. The pathological changes of rat retina were observed electron microscopically. Results We observed the apparent damages of neuron structure in retina of rats exposed to discontinuous acute hypoxia, but the taurine nutritional intervention could lighten the retina damage of rats exposed to acute hypoxia. The taurine nutritional intervention could inhibit the increase of glutamate in retina of rats exposed to simulated 5 000 m high altitude. Conclusion These findings suggest that the taurine nutritional intervention can inhabit the increase of glutamate concentration in retina and can also protect the damage of retina in rats exposed to 5 000 m high altitude.