血管活性肠肽对肺表面活性物质结合蛋白A表达的影响

INFLUENCE OF VASOACTIVE INTESTINAL PEPTIDE ON EXPRESSION OF PULMONARY SURFACTANT ASSOCIATED PROTEIN A IN LUNG EXPLANTS

目的 :研究血管活性肠肽 (VIP)对肺表面活性物质结合蛋白A(SP A)表达的影响以及VIP调控SP A表达的细胞内信号转导途径。方法 :运用免疫组织化学和RT PCR技术研究VIP对SP A表达的影响 ;并进一步运用受体拮抗、蛋白激酶抑制、反义寡核苷酸阻断等手段探讨VIP促进SP A表达的信号转导途径。结果 :①VIP(10 -8mol/L)促进肺泡Ⅱ型细胞 (ATⅡ )细胞中的SP A蛋白表达和提高肺组织SP AmRNA含量 :②VIP受体拮抗剂 (10 -6mol/L)可取消VIP(10 -8mol/L)促进SP A表达的效应 ;③蛋白激酶C抑制剂H7(10 -5mol/L)和c fos基因的反义寡核苷酸 (9× 10 -6mol/L)均可阻断VIP促进SP A表达的作用。结论 :VIP通过其受体促进SP A的表达 ,PKC及c fos蛋白在介导VIP促进SP A表达的细胞内信号转导过程中起重要作用。

Aim: To study the influence of VIP on the expression of SP-A and its intracellular signal transduction pathway. Methods: The influence of VIP on the expression of SP-A was studied by immunohistochemistry and RT-PCR. The intracellular signal transduction pathway was further investigated by using receptor antagonist, protein kinase inhibitor and antisense oligonucleotides. Results: ①VIP(10 -8 mol/L) enhanced SP-A protein expression in alveolar typeⅡ cells(ATⅡ) and increased the content of SP-A mRNA in lung tissue. ②VIP receptor antagonist[D-P-C1-Phe (6) -Leu (17) ]-VIP (10 -6 mol/L) could suppress the VIP-induced expression of SP-A protein and SP-A mRNA. ③c-fos antisense oligonucleotides(9×10 -6 mol/L) could inhibit the VIP-induced expression of SP-A protein and SP-A mRNA. ④ Protein kinase C(PKC) inhibitor H7(10 -5 mol/L) could also depress the VlP-induced SP-A protein and SP-A mRNA. Conclusion: VIP can up-regulate the expression of SP-A through its receptor. PKC and c-fos protein play important roles in the intracellular signal transduction pathway through which VIP induces the expression of SP-A.