Force-generating capacity and contractile protein content of arterial smooth muscle.
Force-generating capacity and contractile protein content of arterial smooth muscle.
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DOI：
10.1085/jgp.64.6.691
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发表时间：
1974-12
期刊：
影响因子：
--
通讯作者：
Megerman J
中科院分区：
文献类型：
--
作者：
Murphy RA;Herlihy JT;Megerman J
根据电子显微照片确定细胞外间隙为40%并进行校正后，由猪颈动脉中膜制备的肌条所产生的最大等长张力（2.2×10⁶达因/平方厘米）可外推得出该肌条平滑肌成分的值为3.7×10⁶达因/平方厘米。对平滑肌细胞的肌球蛋白含量进行了三次独立估算，依据如下：（a）彻底提取和纯化，并估算制备过程中的损失；（b）中膜匀浆的肌球蛋白催化的ATP酶活性；（c）十二烷基硫酸钠处理的中膜匀浆圆盘电泳后，对含肌球蛋白、肌动蛋白和原肌球蛋白的峰进行定量光密度测定。结果一致，得出肌球蛋白含量为5 - 10毫克/克中膜，或8 - 17毫克/克细胞。方法（c）得出肌球蛋白∶肌动蛋白∶原肌球蛋白的重量比为1∶3.2∶0.8。尽管平滑肌细胞产生的实测张力超过哺乳动物的横纹肌，但平滑肌中的肌球蛋白含量约低五倍。平滑肌的肌动蛋白含量相对较高。肌动蛋白和肌球蛋白含量与血管平滑肌电子显微照片中观察到的粗细丝比例相符。
After correction for extracellular space (40%) determined from electron micrographs, the maximum isometric force developed by strips prepared from the media of the hog carotid artery (2.2 x 106 dyn/cm2) can be extrapolated to give a value of 3.7 x 106 dyn/cm2 for the smooth muscle component of the strip. Three independent estimates of the myosin content of the smooth muscle cells were made based on (a) exhaustive extraction and purification with estimates of preparative losses, (b) the myosin catalyzed ATPase activity of media homogenates, and (c) quantitative densitometry of the peaks containing myosin, actin, and tropomyosin after disk electrophoresis of sodium dodecyl sulfate-treated media homogenates. The results were consistent and gave a myosin content of 5–10 mg/g media, or 8–17 mg/g cell. Method (c) gave myosin:actin:tropomyosin weight ratios of 1:3.2:0.8. Although measured force developed by the smooth muscle cell exceeds that of mammalian striated muscle, the myosin content in smooth muscle is about five times lower. The actin content of smooth muscle is relatively high. The actin and myosin contents are consistent with thick and thin filament ratios observed in electron micrographs of vascular smooth muscle.
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影响因子：
3.8
作者：
BARR, L;BOHR, DF;HEADINGS, VE
通讯作者：
HEADINGS, VE
影响因子：
6.7
作者：
GLYNN, IM
通讯作者：
GLYNN, IM
DOI：
10.1007/bf02119385
发表时间：
1960-06-01
期刊：
Archiv fur Kreislaufforschung
影响因子：
--
作者：
LASZT, L
通讯作者：
LASZT, L
影响因子：
--
作者：
MURPHY, RA
通讯作者：
MURPHY, RA
影响因子：
--
作者：
HEADINGS, VE;RONDELL, PA;BOHR, DF
通讯作者：
BOHR, DF