Endothelin-1 alters the contractile phenotype of cultured embryonic smooth muscle cells.
Endothelin-1 alters the contractile phenotype of cultured embryonic smooth muscle cells.
复制标题
Endothelin-1 改变培养的胚胎平滑肌细胞的收缩表型。
DOI：
10.1161/01.res.80.6.885
复制
发表时间：
1997
影响因子：
20.1
通讯作者：
Brozovich,F
中科院分区：
文献类型：
--
作者：
Fisher,SA;Ikebe,M;Brozovich,F
平滑肌组织可分为阶段性（快）或紧张性（慢）收缩表型。本研究旨在研究发育过程中这些表型的特异性以及生长因子在此过程中的作用。我们使用肌球蛋白轻链17（MLC 17）和肌球蛋白重链转录剪接变异体作为鸡胚强直性（主动脉）和阶段性（肠）平滑肌表型的标志物。通过逆转录-聚合酶链反应，我们确定胚胎第6至16天是建立这些表型的关键时期。在此期间，内皮素-1在主动脉中的水平比肠组织高40倍。为了验证内皮素-1可能参与建立主动脉（紧张性）表型的假设，我们开发了一个系统，其中胚胎平滑肌细胞在体外表现出阶段性和紧张性收缩特性。单细胞力测量结果显示，培养的胚胎砂囊（相位）细胞对去极化的反应更快（8±2秒），并且比培养的胚胎主动脉（强直）细胞（20±0.7秒，0.76±0.01 μN;P<0.05）获得更大的力（3.0±0.7 μN）。阶段性（砂囊）细胞长期暴露于内皮素-1延长了达到峰值力的时间（24±3秒）并降低了峰值力（1.0±0.1 μN），因此收缩类似于强直型。这种效应由内皮素-A受体介导，与MLC 17剪接向强直模式的转变有关。这些结果表明，内皮素-1是高度富集在发展中的主动脉与肠组织相比，可以转换阶段性平滑肌细胞的紧张型在体外，这表明在发展过程中，这种生长因子在确定平滑肌细胞的收缩表型的作用。
Smooth muscle tissues may be classified into phasic (fast) or tonic (slow) contractile phenotypes. This study was initiated to examine the specification of these phenotypes during development and the role of growth factors in this process. We used myosin light chain 17 (MLC17) and myosin heavy chain transcript splice variants as markers of the tonic (aortic) and phasic (intestinal) smooth muscle phenotypes in chick embryos. By reverse transcription–polymerase chain reaction, we determined embryonic days 6 to 16 to be a critical period for the establishment of these phenotypes. During this period, endothelin-1 is present at 40-fold-higher levels in aortic compared with intestinal tissues. To test the hypothesis that endothelin-1 may be involved in establishing the aortic (tonic) phenotype, we developed a system in which embryonic smooth muscle cells exhibit phasic and tonic contractile properties in vitro. Single-cell force measurements showed that cultured embryonic gizzard (phasic) cells developed force more rapidly (8±2 seconds) and achieved greater force (3.0±0.7 μN) than did cultured embryonic aortic (tonic) cells (20±0.7 seconds, 0.76±0.01 μN;P<.05) in response to depolarization. Chronic exposure of the phasic (gizzard) cells to endothelin-1 prolonged the time to peak force (24±3 seconds) and reduced the peak force (1.0±0.1 μN), so that the contraction resembled the tonic type. This effect, mediated by the endothelin-A receptor, was associated with a shift in MLC17splicing to the tonic pattern. These results demonstrate that endothelin-1 is highly enriched in developing aortic compared with intestinal tissues and can convert phasic smooth muscle cells to the tonic type in vitro, suggesting a role for this growth factor during development in determining the contractile phenotype of smooth muscle cells.