Identification and their function of paraquat-induced unknown genes in rat lungs.

本工作的目的是评估大鼠肺部暴露于PQ早期阶段受氧化应激调节的基因的影响。用20 mg/kg PQ处理大鼠3 h，立即切除肺。在我们的实验条件下，2周后观察到显著的肺损伤。1）在第一年，我们对两个基因特别感兴趣，TAFIIB和Lpin2。它们在Clara细胞和肺泡巨噬细胞中强烈可见。这些发现表明，转录水平和脂质代谢在克拉拉细胞和巨噬细胞中被激活的可能性，导致它们在PQ驱动的肺损伤的发生中发挥关键作用。2）第二年，采用差异显示-PCR方法分离得到19个分化克隆。最终确定有四个克隆受到显著影响。它们是血浆磷脂转移蛋白（PLTP）、亲乳素、全血影蛋白和一个未知基因。我们显示了肺组织中亲乳素mRNA表达的分布。3）第三年，利用cDNA阵列膜，我们发现PQ暴露产生了29个差异表达的基因（> 1.5倍）。对部分阳性基因进行实时荧光定量PCR检测。PDGF、硫氧还蛋白、谷胱甘肽S-转移酶、SOD的表达均显著上调，提示氧自由基是PQ中毒的主要原因。此外，一些CYP2C6、2C7、2C12、2C13等代谢酶也受到明显影响。表情的刺激是肺所特有的，而不是肝和肾。这些结果表明，他们参与了PQ引起的严重肺损伤的发病。

The aim of the present work was to evaluate the implications for genes that are regulated by oxidative stress at the early stage of PQ exposure in rat lungs. Rats were treated with 20mg/kg PQ for 3 h, and the lungs were immediately excised. Significant pulmonary injury was observed after 2 weeks under our experimental conditions. 1)In the first year, we were particularly interested in two genes, TAFIIB and Lpin2. They were strongly visualized in Clara cells and in alveolar macrophages. These findings suggest the possibility that transcription levels and lipid metabolism are activated in Clara cells and in macrophages, resulting in their playing a crucial role at the onset of PQ-driven pulmonary injury. 2)In the second year, 19 differentiated clones were isolated by differential display-PCR method. Four clones were finally determined to be significantly affected. They were plasma phospholipid transfer protein(PLTP), lactrophiline, all-spectrin and one unknown gene. We showed the distribution of mRNA expression of lactrophiline in lung tissues. 3)In the third year, using cDNA array membrane, we found that PQ exposure gave 29 genes differentially expressed(>1.5-fold). Some positive genes were further validated and quantitated with real-time RT-PCR. The expressions of PDGF, thioredoxin, glutathione S-transferase, SOD were significantly up-regulated, suggesting that the oxygen free radicals were major contributors to the onset of PQ poisoning. In addition, some CYP members (CYP2C6,2C7,2C12,2C13) were remarkably affected. The stimulation of expressions was peculiar to lungs, and not to liver and kidneys. These results suggest that they are involved in the onset of PQ-induced serious pulmonary injury.