大鼠内毒素性肺损伤中肺α_1和β受体的变化

Changes of pulmonary α_1-and β-adrenergic receptors during endotoxin-induced acute lung injury in rats

本研究动态观察大鼠内毒素性肺损伤中肺α１－和β－ＡＲ的变化，以探讨肺ＡＲ变化与急性肺损伤的关系及其机制。结果表明，内毒素诱导大鼠急性肺损伤过程中，肺α１－ＡＲ和β－ＡＲ的Ｂｍａｘ值均明显降低（下调），分别较对照组下降３５和４３％。β－ＡＲ下调可能是导致急性肺损伤的原因之一；α－ＡＲ下调则是一种保护性反应。活性氧在肺ＡＲ下调中起重要作用，而循环血去甲肾上腺素和肾上腺素水平的升高不是其主要因素。

Changes of pulmonary α_1-and β-adrenergic receptor (α_1-AR and β-AR)during endotoxin-induced acute lung injury in rates were oberved to find out the rela-tionship between them and the mechanism of change. Results showed that there was amarked decrease of B_max of both α_1-AR and β-AR by 35% and 43% respectively, dur-ing acute lung injury. The down regulation of β-AR might be one of causes of acutelung injury while that of α_1-AR seems to be a protective response. Active oxygen playedan important role in endotoxin-induced down regulation of AR in the rat lungs. The increa-sed level of norepinephrine and epinephrine was not the main factor that initiate the downregulation of AR. Intravenous injection of tumor necrosis factor (5×10~6U/kg ) exerts noiafluence on the changes of pulmonary AR in rats.