谷氨酸致小鼠急性损伤的实验性研究

Experimental study of acute lung injury induced by glutamate in vivo

目的:观察谷氨酸(glutamate,Glu)的肺损伤效应。方法:测定肺湿重/体质量、肺湿重/肺干重(W/D)、肺泡灌洗液中细胞和蛋白漏出量,并观察肺显微形态的变化。结果:(1)Glu(0.50～0.75g/kg)处理2h后小鼠肺湿重/体质量、W/D、肺泡灌洗液中白细胞、红细胞和蛋白漏出量以剂量依赖方式增加;(2)病理切片显示Glu作用2h后肺组织呈炎症改变,有大量的中性粒细胞浸润;(3)NMDA受体阻断剂MK-801(0.1mg/kg)预处理30min可抑制Glu(0.50g/kg)引起的W/D的升高(P<0.05)。结论:Glu通过激活NMDA受体可引起急性肺损伤。

Objective To investigate the possible injury induced by glutamate in the lung. Methods The lung wet weight/body weight （LW/BW） , lung wet/dry weight （W/D） , the content of cells and the total protein （TP） in bronchoalveolar lavage fluid （BALF） were determined together with the micromorphology observation. Results （ 1 ） The LW/BW, W/D, the content of white blood ceils, red blood cells and TP in BALF increased in a dose dependent manner 2 hours after the administration of the glutamate （0.50 -0.75 g/kg）. （2） Examination of histological sections showed the presence of lung inflammation charactered by neutrophils recruitment 2 hours after the glutamate administration. （3） The increase of W/D caused by glutamate （0.50 g/kg） was nearly abolished by pre-treatment with MK801 （a specific blocker of NMDA receptor, 0.1 mg/kg） for 30 minutes （P 〈 0.05 ）. Conclusion Glutamate can cause the acute lung injury through the activation of NMDA receptor in vivo.