NF- kB 对低氧大鼠肺动脉平滑肌细胞ET- 1 表达的影响

目的：探讨核因子kB（NF—kB）对低氧大鼠肺动脉平滑肌细胞（PAMSC）内皮素-1（endothelin—1，ET—1）表达的影响。方法：分离培养大鼠肺动脉平滑肌细胞，分别在常氧和低氧条件下培养48小时。ELISA检测培养上清中ET—1含量，RT—PCR检测ET-1 mRNA表达。在培养液中加入NF—kB抑制剂PDTC，检测PASMCs ET—1表达的变化。Western blotting检测PASMCs IkB表达变化。结果：低氧培养能够诱导PASMCs表达ET—1。NF—kB抑制剂能够减少由于低氧引起的ET—1释放，IkB在低氧情况下表达明显减少。结论：ET-1低氧情况下在PAMCS表达明显增加。可能参与低氧所引起的肺动脉的病理过程。低氧所引起的ET—1表达增加可能通过NF—kB信号通路。

Effect of NF- kB on ET- 1 Expression in PASMCs of Rats under Hypoxia

Objective: To study the effects of the nuclear factor kappa B(NF-kB) in the endothelin-1(ET-1) expression in the PASMCs of rats under hypoxia.Methods: 28 male Wistar rats were selected and their PASMCs were isolated and incubated at normal situation or under hypoxia for 48 hours.The ET-1 level in the supernatant was detected by ELISA.RT-PCR was used to investigate the mRNA expression of ET-1 in the PASMCs.The IkB,which is the most prominent indicator of activation of NF-kB,was detected by Western blotting in the PASMCs.The inhibitor of NF-kB(10uM),PDTC,was added to the culture to investigate the effect of it on the expression of ET-1.Results: The ET-1 expression can be induced significantly in the hypoxia situation.The inhibitor of NF-kB can decrease the expression of ET-1 induced by hypoxia.The IkB expression decreased significantly under hypoxia.Conclusion: The expression of ET-1 increased obviously in the PASMCs under hypoxia,which may participate in the pathological events of the PASMCs in the hypoxia situation and contribute to the activation of NF-kB signal pathway.So inhibiting NF-kB activation could be a new therapy for pulmonary artery hypertension induced by hypoxia.