Cohen D M, Murphy R A
Circ Res. 1979 Nov;45(5):661-5. doi: 10.1161/01.res.45.5.661.
We estimated the cellular myosin, actin, and tropomyosin contents of vascular smooth muscle from (1) seven major arteries, (2) seven large veins, and (3) the first through third order branches of the uterine vasculature to determine whether variations in the contractile apparatus contribute to the functional diversity of vascular smooth muscle. We obtained the estimates by quantitative densitometry of stained polyacrylamide gels after electrophoresis of sodium dodecyl sulfate-treated tissue homogenates. No differences in cellular myosin content were found (18.7 +/- 1.0 mg/g cell wet weight in arteries vs. 17.2 +/- 0.7 in veins). However, the actin and tropomyosin contents were higher in arteries (49.7 +/- 2.9 and 13.1 +/- 0.8 mg/g cell, respectively) than in veins (25.5 +/- 1.4 and 7.0 +/- 0.3 mg/g cell). These differences persisted in the smaller uterine vessels. The higher contents of thin filament proteins in arteries, compared with veins and several other smooth muscle tissues previously studied, may underlie the high force generating capacity of arterial smooth muscle.
我们估计了来自以下部位的血管平滑肌细胞中的肌球蛋白、肌动蛋白和原肌球蛋白含量：(1) 七条主要动脉，(2) 七条大静脉，以及 (3) 子宫血管系统的一级至三级分支，以确定收缩装置的变化是否有助于血管平滑肌的功能多样性。我们通过对十二烷基硫酸钠处理的组织匀浆进行电泳后，对染色的聚丙烯酰胺凝胶进行定量光密度测定来获得估计值。未发现细胞肌球蛋白含量存在差异（动脉中为18.7±1.0mg/g细胞湿重，静脉中为17.2±0.7mg/g细胞湿重）。然而，动脉中的肌动蛋白和原肌球蛋白含量（分别为49.7±2.9和13.1±0.8mg/g细胞）高于静脉（分别为25.5±1.4和7.0±0.3mg/g细胞）。这些差异在较小的子宫血管中持续存在。与静脉和先前研究的其他几种平滑肌组织相比，动脉中细肌丝蛋白含量较高，这可能是动脉平滑肌高力量产生能力的基础。
