钙激活的肌动蛋白结合蛋白对去表皮平滑肌力学性能的影响。

Influence of Ca-activated brevin on the mechanical properties of skinned smooth muscle.

作者信息

Gailly P, Gillis J M, Capony J P

机构信息

Department of Physiology, University of Louvain, Bruxelles, Belgium.

出版信息

Adv Exp Med Biol. 1993;332:205-10; discussion 210-2. doi: 10.1007/978-1-4615-2872-2_19.

DOI:10.1007/978-1-4615-2872-2_19

PMID:8109334

Abstract

Solutions of purified brevin were applied to skinned thin bundles or isolated fibres of smooth muscle. This produced a sharp drop of isometric tension, an effect due to the severing effect of brevin on actin filaments, partially depleted from tropomyosin in skinned preparations. On skinned single fibres, brevin accelerates the speed of unloaded shortening. As no effect was detected on the myofibrillar ATPase turnover rate, brevin was thought to affect the viscosity of the cytoplasm. This was confirmed by analysis of the cytoplasm stiffness which decreased in the presence of brevin. It is proposed that Ca-activated brevin acts on actin-filamin gels, set in parallel to the contractile apparatus.

摘要

将纯化的短肌动蛋白（brevin）溶液应用于去膜的平滑肌细束或分离的纤维。这导致等长张力急剧下降，这种效应是由于短肌动蛋白对肌动蛋白丝的切断作用，在去膜制剂中肌动蛋白丝部分缺乏原肌球蛋白。在去膜单纤维上，短肌动蛋白加速了无负荷缩短的速度。由于未检测到对肌原纤维ATP酶周转率的影响，推测短肌动蛋白会影响细胞质的粘度。通过分析在短肌动蛋白存在下细胞质硬度降低的情况证实了这一点。有人提出，钙激活的短肌动蛋白作用于与收缩装置平行设置的肌动蛋白-细丝蛋白凝胶。