García-Sáinz J A, Alcántara-Hernández R, Vázquez-Prado J
Instituto de Fisiología Celular, Universidad Nacional Autónoma de México, Mexico DF.
Eur J Pharmacol. 1998 Jan 26;342(2-3):311-7. doi: 10.1016/s0014-2999(97)01465-9.
Noradrenaline increased the mRNA levels of c-fos and c-jun in rat-1 fibroblast lines stably expressing the cloned alpha1-adrenoceptor subtypes. The efficacy to induce the expression of c-fos mRNA was similar for the three cell lines (alpha1d = alpha1b = alpha1a) but different for c-jun (alpha1a > or = alpha1b > alpha1d). The EC50 values were also different: approximately 5 nM (c-fos) and approximately 300 nM (c-jun) for cells transfected with the alpha1a subtype, approximately 30 nM (c-fos) and approximately 300 nM (c-jun) for cells transfected with the alpha1b subtype and approximately 300 nM (c-fos and c-jun) for those transfected with the alpha1d subtype. Staurosporine and protein kinase C down-regulation blocked such effects, indicating a role of this protein kinase. Endothelin-1 (10 nM) also increased the levels of c-fos and c-jun mRNAs. These actions of endothelin-1 were unaffected by staurosporine and protein kinase C down-regulation. It is concluded that activation of any of the three cloned subtypes can increase the levels of c-fos and c-jun mRNAs and that protein kinase C plays a major role in mediating such effects.
去甲肾上腺素可增加稳定表达克隆的α1 -肾上腺素能受体亚型的大鼠-1成纤维细胞系中c - fos和c - jun的mRNA水平。三种细胞系（α1d = α1b = α1a）诱导c - fos mRNA表达的效力相似，但诱导c - jun表达的效力不同（α1a≥α1b＞α1d）。半数有效浓度（EC50）值也不同：转染α1a亚型的细胞，c - fos约为5 nM，c - jun约为300 nM；转染α1b亚型的细胞，c - fos约为30 nM，c - jun约为300 nM；转染α1d亚型的细胞，c - fos和c - jun均约为300 nM。星形孢菌素和蛋白激酶C下调可阻断此类效应，表明该蛋白激酶发挥了作用。内皮素-1（10 nM）也可增加c - fos和c - jun mRNA的水平。内皮素-1的这些作用不受星形孢菌素和蛋白激酶C下调的影响。结论是，三种克隆亚型中任何一种的激活均可增加c - fos和c - jun mRNA的水平，且蛋白激酶C在介导此类效应中起主要作用。
