Morishita R, Gibbons G H, Pratt R E, Tomita N, Kaneda Y, Ogihara T, Dzau V J
Division of Cardiovascular Medicine, Falk Cardiovascular Research Center, Stanford University School of Medicine, California 94035.
J Clin Invest. 1994 Aug;94(2):824-9. doi: 10.1172/JCI117402.
In addition to the atria, recent evidence suggests that atrial natriuretic peptide (ANP) is also synthesized in other tissues. Of particular interest is the location of ANP mRNA in the vessel wall. We and others have shown that exogenously added ANP inhibited the growth of endothelial cells and vascular smooth muscle cells (VSMC) in culture. However, it is not known if the locally synthesized ANP would act similarly. Because cultured endothelial cells and VSMC have lost the ability to express the endogenous ANP gene, we have transfected cells in culture with an expression vector expressing rat ANP and have examined the effects on growth. Cultured endothelial cells transfected with an ANP expression vector synthesized and secreted high levels of ANP. These cells also showed significantly lower rates of DNA synthesis under basal and fibroblast growth factor (FGF)-stimulated conditions. Addition of conditioned medium from endothelial cells transfected with ANP vector to nontransfected endothelial cells resulted in the significant increase in cyclic GMP. Similarly, conditioned media collected from endothelial cells transfected with ANP vector also decreased DNA synthesis in VSMC. Coculture of ANP-transfected endothelial cells with quiescent VSMC showed that released ANP from endothelial cells inhibited DNA synthesis in VSMC. Finally, we examined the autocrine effect of direct transfection of ANP vector into VSMC. Transfection of the ANP vector decreased DNA synthesis in VSMC under basal and angiotensin II-stimulated conditions. Similarly, transfection of the ANP vector resulted in a decrease in the PDGF and serum (5%)-stimulated DNA synthesis of VSMC. These results demonstrate that endogenously produced ANP can exert autocrine and paracrine inhibitory effects on endothelial cell and VSMC growth. In vivo gene transfer of ANP may provide us with the opportunity of gene therapy for vascular diseases in which the abnormalities are vasoconstriction and pathological growth.
除心房外，最近有证据表明心房利钠肽（ANP）也在其他组织中合成。特别值得关注的是ANP mRNA在血管壁中的定位。我们和其他人已经表明，外源性添加的ANP可抑制培养的内皮细胞和血管平滑肌细胞（VSMC）的生长。然而，尚不清楚局部合成的ANP是否会有类似作用。由于培养的内皮细胞和VSMC已失去表达内源性ANP基因的能力，我们用表达大鼠ANP的表达载体转染培养中的细胞，并研究其对生长的影响。用ANP表达载体转染的培养内皮细胞合成并分泌高水平的ANP。这些细胞在基础条件和成纤维细胞生长因子（FGF）刺激条件下的DNA合成率也显著降低。将用ANP载体转染的内皮细胞的条件培养基添加到未转染的内皮细胞中，导致环磷酸鸟苷显著增加。同样，从用ANP载体转染的内皮细胞收集的条件培养基也降低了VSMC中的DNA合成。将转染ANP的内皮细胞与静止的VSMC共培养表明，内皮细胞释放的ANP抑制了VSMC中的DNA合成。最后，我们研究了将ANP载体直接转染到VSMC中的自分泌作用。在基础条件和血管紧张素II刺激条件下，转染ANP载体降低了VSMC中的DNA合成。同样，转染ANP载体导致VSMC中血小板衍生生长因子（PDGF）和血清（5%）刺激的DNA合成减少。这些结果表明，内源性产生的ANP可对内皮细胞和VSMC的生长发挥自分泌和旁分泌抑制作用。ANP的体内基因转移可能为我们提供对血管疾病进行基因治疗的机会，这些疾病的异常表现为血管收缩和病理性生长。
