Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Echinobase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
Echinobase
ECB-ART-35228
Cell Tissue Res 1982 Jan 01;2221:11-24. doi: 10.1007/bf00218285.
Show Gene links Show Anatomy links

Physiological and cytochemical studies on activator calcium in contraction by smooth muscle of a sea cucumber, Isostichopus badionotus.

Suzuki S .


???displayArticle.abstract???
The physiological properties of mechanical responses and the intracellular localization and translocation of calcium as a pyroantimonate precipitate were studied in the longitudinal retractor muscle (LRM) of a Bermuda sea cucumber. Acetylcholine (ACh)-induced contraction was reduced by lowering the external Ca concentration, and suppressed completely by prolonged soaking in Ca-free solution. The magnitude of ACh-induced contraction was decreased by Mn and La ions. Furthermore, procaine reduced the ACh-induced contraction. The complete removal of Ca and Mg ions from the external medium induced a so called Ca . Mg-removal contraction. Electron microscopically, numerous subsarcolemmal vesicles were observed in the LRM fibers. In the resting fibers, pyroantimonate precipitates were localized in the subsarcolemmal vesicles and along the inner surface of plasma membrane. While, in the fiber fixed during mechanical activity, the pyroantimonate precipitates were decreased remarkably in the subsarcolemmal vesicles and at the plasma membrane, and diffusely distributed in the myoplasm. Electron-probe X-ray microanalysis showed that the precipitate contains Ca in a significant amount. These results indicate that the contraction of the LRM fibers is caused not only by Ca-influx but also by Ca-release from the intracellular storage sites, such as the subsarcolemmal vesicles and the inner surface of plasma membrane.

???displayArticle.pubmedLink??? 7060087
???displayArticle.link??? Cell Tissue Res


Genes referenced: LOC100887844

References [+] :
Atsumi, Localization of calcium-accumulating structures in the anterior byssal retractor muscle of Mytilus edulis and their role in the regulation of active and catch contractions. 1976, Pubmed