@article{oai:kanagawa-u.repo.nii.ac.jp:00006920,
 author = {木南, 雅暁 and Kinami, Masaaki and 鈴木, 季直 and Suzuki, Suechika},
 journal = {Science Journal of Kanagawa University},
 month = {May},
 note = {The ultrastructure of dyads in the longitudinal body wall muscle (LBWM) of a mollusc Dolabella auricularia was studied to elucidate electro-mechano coupling in the dyadic contacts of somatic smooth muscles, and to make clear the morphological homology with the triadic contacts of skeletal muscles. In LBWM fibers, the sarcoplasmic reticulum (SR) in vesicular forms was mostly located underneath the plasma membrane, and constructed dyads, not only along the fiber surface but also around the tubular invaginations (Sugi and Suzuki, 1978)^<1)> which resemble the transverse tubule of skeletal muscles in shape. In the junctional gap of dyads, electron-dense foot-like structures were arrayed at regular intervals. In dyads found along the fiber surface, the diameter of the foot-like structures was 18.3nm, the center-to-center distance was 30.5nm, and the junctional gap was 9.7nm. While, in triads found around the tubular invaginations, those dimensions were 18.6nm, 30.4nm and 9.6nm, respectively. No significant difference was found between the respective dimensions of the two types of dyads, indicating that they are fundamentally the same in construction. On the other hand, the measured dimensions of dyadic contacts coincided well with those of the triadic contacts of skeletal muscles. Furthermore, as found in skeletal muscle triads, a two-dimensional orthogonal array of foot-like structures on the SR junctional membrane was also confirmed by observing serial sections 35nm thick. These results indicate that the foot-like structures are truly feet, and the dyadic contacts of LBWM fibers are homologous in structure and possibly in function with the triadic contacts of skeletal muscles. This view was further supported by these experiments, proving the existence of calsequestrin in SR demonstrated by immunoelectron microscopy and the high quantity (3.02%) of fractional SR volume per fiber volume measured by the montage method.},
 pages = {21--30},
 title = {軟体動物タツナミガイ体壁縦走筋ダイアッド接合部の構造解析},
 volume = {17},
 year = {2006}
}