脂多糖对大鼠肺间质巨噬细胞CCK受体mRNA表达的影响

目的：探讨胆囊收缩素(cholecystokinin，CCK)受体CCK—AR及CCK—BRmRNA在大鼠肺间质巨噬细胞(PIMs)内的表达及脂多糖(1ipopolysaccharide，LPS)对其表达的影响。方法：用酶消化法结合肺泡灌洗和肺循环灌洗技术分离纯化大鼠PIMs，用LPS(10mg／L)孵育PIMs0．5～12h。采用RT—PCR及Southern印迹技术观察CCK受体在大鼠PIMs内的表达亚型及LPS对其表达的影响。结果：经RT—PCR检测显示，CCK—AR和CCK—BRmRNA在大鼠PIMs均有表达，CCK—ARmRNART—PCR扩增产物为1．37kb，CCK—BRmRNART—PCR扩增产物为480bp。CCK—BRmRNA的相对表达量高于CCK—AR；LPS作用2h可明显诱导2种CCK受体mRNA表达上调，至12h仍维持较高水平。用γ-^32P—ATP标记的两种特异性探针分别对CCK—AR和CCK—BRmRNART—PCR扩增产物进行Southern分子杂交，结果均有特异性杂交带出现。结论：肺间质巨噬细胞有CCK—AR和CCK—BRmRNA表达，LPS可诱导2种CCK受体mRNA表达上调。

Effect of lipopolysaccharides on expression of cholecystokinin receptor mRNA in rat pulmonary interstitial macrophages

Objective: To investigate the expression of cholecystokinin (CCK) receptor mRNA and the effect of lipopolysaccharides(LPS) on its expression in rat pulmonary interstitial macrophages (PIMs). Methods: The PIMs isolated from rat lung tissues were purified by the collagenase digestion method combined with alveolar lavage and pulmonary vessel perfusion, and incubated with LPSQO mg/L) for 0. 5-12 h. The subtypes of CCK receptor and the effects of LPS on its expression were investigated by RT-PCR and Southern blot analysis in rat PIMs. Results: CCK-AR and CCK-BR mRNA were detected in rat PIMs by means of RT-PCR; their amplification products were approximately 1. 37 kb and 480 bp,respectively. The expression of CCK-BR mRNA was higher than that of CCK-AR mRNA,and the expression of CCK-AR and CCK-BR mRNA could be up-regulated obviously by LPS incubation for 2 to 12 h. r-32P-ATP 5'-end-labelled probes showed specific hybridization bands by Southern blot analysis of CCK-AR and CCK-BR mRNA products. Conclusion: There are CCK-AR and CCK-BR mRNA expressions in rat PIMs and the expressions can be up-regulated by LPS.