title: The unique organization of filamentous actin in the medullary canal of the medulla oblongata.
abstract: In the central canal, F-actin is predominantly localized in the apical region, forming a ring-like structure around the circumference of the lumen. However, an exception is found in the medulla oblongata, where the apical F-actin becomes interrupted in the ventral aspect of the canal. To clarify the precise localization of F-actin, the fluorescence signals for F-actin were converted to the peroxidase/DAB reaction products in this study by a phalloidin-based ultrastructural technique, which demonstrated that F-actin is located mainly in the microvilli and terminal webs in the ependymocytes. It is because the ventrally oriented ependymocytes do not possess well-developed microvilli or terminal web that led to a discontinuous labeling of F-actin in the medullary canal. Since spinal motions can change the shape and size of the central canal, we next examined the cytoskeletons in the medullary canal in both rats and monkeys, because these two kinds of animals show different kinematics at the atlanto-occipital articulation. Our results first demonstrated that the apical F-actin in the medullary canal is differently organized in the animals with different head-neck kinemics, which suggests that the mechanic stretching of spinal motions is capable of inducing F-actin reorganization and the subsequent cell-shape changes in the central canal.
authors.affiliation: Laboratory Teaching Center of Basic Medicine, Norman Bethune Health Science Center of Jilin University, Changchun, Jilin Province, 130021, PR China.
authors.forename: Bai-Hong
authors.initials: BH
authors.lastname: Tan
authors.affiliation: Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun, Jilin Province, 130021, PR China.
authors.forename: Chun-Yan
authors.initials: CY
authors.lastname: Guo
authors.affiliation: Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun, Jilin Province, 130021, PR China.
authors.forename: Tian-Qing
authors.initials: TQ
authors.lastname: Xiong
authors.affiliation: Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun, Jilin Province, 130021, PR China.
authors.forename: Ling-Meng
authors.initials: LM
authors.lastname: Chen
authors.affiliation: Department of Histology and Embryology, College of Basic Medical Sciences, Norman Bethune Health Science Center of Jilin University, Changchun, Jilin Province, 130021, PR China. Electronic address: liyanchao@jlu.edu.cn.
authors.forename: Yan-Chao
authors.initials: YC
authors.lastname: Li
mesh_terms: D008841:Actin Cytoskeleton / Q000378:metabolism / Q000648:ultrastructure*; D000199:Actins / Q000302:isolation & purification / Q000378:metabolism*; D000818:Animals; D001696:Biomechanical Phenomena; D000882:Haplorhini; D008526:Medulla Oblongata / Q000378:metabolism / Q000648:ultrastructure*; D051381:Rats; D013115:Spinal Canal / Q000378:metabolism / Q000648:ultrastructure*
chemical_list: D000199:Actins
keywords: Confocal microscopy; Cytoskeleton; Electron microscopy; Ependyma; F-actin; Medulla oblongata