一氧化氮抑制血管紧张素Ⅱ和内皮素-1诱导的心肌细胞原癌基因c-fos表达(英文)

Nitric oxide inhibits the expression of proto-oncogene c-fos induced by angiotensinⅡand endothelin-1 in cardiomyocytes

在原代培养的新生大鼠心肌细胞上 ,探讨一氧化氮 (NO)对血管紧张素Ⅱ (AⅡ )和内皮素 1(ET 1)诱导的心肌细胞肥大和原癌基因c fos表达的影响。用Bradford法测定心肌细胞总蛋白含量 (作为心肌细胞肥大的指标 ) ;用基因特异性引物和SuperScript一步法进行逆转录聚合酶链式反应 (RT PCR) ,检测大鼠心肌细胞原癌基因c fos的表达 (以GAPDH为内标 )。结果显示 ,AⅡ和ET 1分别作用 5d和 3d后 ,心肌细胞总蛋白含量显著增加 ;硝普钠 (NO供体 )可抑制AⅡ或ET 1诱导的心肌细胞总蛋白增加。AⅡ ,ET 1和PMA (蛋白激酶C激动剂 )均可诱导心肌细胞原癌基因c fos的表达 ;L 精氨酸可抑制AⅡ ,ET 1和PMA诱导心肌细胞原癌基因c fos的表达 ,L NAME(NOS抑制剂 )可抑制L 精氨酸的这一作用 ;硝普钠对可抑制AⅡ ,ET 1和PMA诱导心肌细胞原癌基因c fos的表达。结果表明 ,NO可抑制AⅡ或ET 1诱导的心肌细胞肥大和原癌基因c fos表达 ,其作用机制可能与蛋白激酶C这一环节有关。

WT5”BZ] The effect of nitric oxide (NO) on the hypertrophic response and the proto oncogene c fos expression induced by angiotensin Ⅱ (AⅡ) or endothelin 1 (ET 1) was investigated in the primary culture of neonatal rat cardiomyocytes. Total protein content of cardiomyocytes (used as the index of cardiac myocyte hypertrophy) was determined by the Bradford method. The proto oncogene c fos expression was assessed using reverse transcription polymerase chain reaction (RT PCR) standardized with glyceraldehyde 3 phosphate dehydrogenase (GAPDH). RT PCR was performed in a single tube using gene specific primers and the SuperScript One Step RT PCR System. Total protein content of cardiomyocytes increased significantly on day 5 after AⅡ treatment or on day 3 after ET 1 treatment and the increased protein content was inhibited by SNP (NO donor). AⅡ, ET 1 and PMA (protein kinase C activator) induced the c fos gene expression of cardiomyocytes, while L arginine inhibited it. The L arginine effect was blocked by L NAME (NOS inhibitor). SNP inhibited the c fos gene expression of cardiomyocytes induced by AⅡ,ET 1 or PMA as well. These results suggest that NO can inhibit the hypertrophic response and the proto oncogene c fos expression of cardiomyocytes induced by AⅡ or ET 1 and the cross link may be located at the site of protein kinase C.