title: Redistribution of Cav2.1 channels and calcium ions in nerve terminals following end-to-side neurorrhaphy: ionic imaging analysis by TOF-SIMS.
abstract: The P/Q-type voltage-dependent calcium channel (Cav2.1) in the presynaptic membranes of motor nerve terminals plays an important role in regulating Ca2+transport, resulting in transmitter release within the nervous system. The recovery of Ca2+-dependent signal transduction on motor end plates (MEPs) and innervated muscle may directly reflect nerve regeneration following peripheral nerve injury. Although the functional significance of calcium channels and the levels of Ca2+signalling in nerve regeneration are well documented, little is known about calcium channel expression and its relation with the dynamic Ca2+ion distribution at regenerating MEPs. In the present study, end-to-side neurorrhaphy (ESN) was performed as an in vivo model of peripheral nerve injury. The distribution of Ca2+at regenerating MEPs following ESN was first detected by time-of-flight secondary ion mass spectrometry, and the specific localization and expression of Cav2.1 channels were examined by confocal microscopy and western blotting. Compared with other fundamental ions, such as Na+and K+, dramatic changes in the Ca2+distribution were detected along with the progression of MEP regeneration. The re-establishment of Ca2+distribution and intensity were correlated with the functional recovery of muscle in ESN rats. Furthermore, the re-clustering of Cav2.1 channels after ESN at the nerve terminals corresponded with changes in the Ca2+distribution. These results indicated that renewal of the Cav2.1 distribution within the presynaptic nerve terminals may be necessary for initiating a proper Ca2+influx and shortening the latency of muscle contraction during nerve regeneration.
authors.affiliation: Department of Anatomy, Faculty of Medicine, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd, Taichung, 40201, Taiwan.|Department of Medical Research, Research Center for Traditional Chinese Medicine, China Medical University Hospital, China Medical University, Taichung, Taiwan.
authors.forename: Chiung-Hui
authors.initials: CH
authors.lastname: Liu
authors.affiliation: Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 11031, Taiwan.
authors.forename: Hung-Ming
authors.initials: HM
authors.lastname: Chang
authors.affiliation: Department of Anatomy, Faculty of Medicine, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd, Taichung, 40201, Taiwan.
authors.forename: To-Jung
authors.initials: TJ
authors.lastname: Tseng
authors.affiliation: Department of Anatomy, Faculty of Medicine, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd, Taichung, 40201, Taiwan.
authors.forename: Chyn-Tair
authors.initials: CT
authors.lastname: Lan
authors.affiliation: Department of Anatomy, Faculty of Medicine, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd, Taichung, 40201, Taiwan.
authors.forename: Li-You
authors.initials: LY
authors.lastname: Chen
authors.affiliation: Department of Anatomy, Faculty of Medicine, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd, Taichung, 40201, Taiwan.
authors.forename: Su-Chung
authors.initials: SC
authors.lastname: Youn
authors.affiliation: Department of Anatomy and Cell Biology, School of Medicine, College of Medicine, Taipei Medical University, Taipei, 11031, Taiwan.|Division of Plastic Surgery, Department of Surgery, Cathay General Hospital, Taipei, 10630, Taiwan.
authors.forename: Jian-Jr
authors.initials: JJ
authors.lastname: Lee
authors.affiliation: Department of Biochemistry, School of Medicine, Taipei Medical University, Taipei, 110, Taiwan.
authors.forename: Fu-Der
authors.initials: FD
authors.lastname: Mai
authors.affiliation: Department of Anatomy, Faculty of Medicine, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd, Taichung, 40201, Taiwan.
authors.forename: Jui-Feng
authors.initials: JF
authors.lastname: Chou
authors.affiliation: Department of Anatomy, Faculty of Medicine, Chung Shan Medical University, No.110, Sec.1, Jianguo N. Rd, Taichung, 40201, Taiwan. khrnangel@gmail.com.|Department of Pediatrics, Shan Medical University Hospital, Taichung, 40201, Taiwan. khrnangel@gmail.com.
authors.forename: Wen-Chieh
authors.initials: WC
authors.lastname: Liao
mesh_terms: D000818:Animals; D002118:Calcium / Q000032:analysis* / Q000378:metabolism*; D020864:Calcium Channels, N-Type / Q000032:analysis* / Q000378:metabolism*; D002413:Cations, Divalent / Q000032:analysis / Q000378:metabolism; D004195:Disease Models, Animal; D008297:Male; D009411:Nerve Endings / Q000378:metabolism* / Q000473:pathology*; D051381:Rats; D017208:Rats, Wistar; D018629:Spectrometry, Mass, Secondary Ion
chemical_list: D002118:Calcium; D020864:Calcium Channels, N-Type; D002413:Cations, Divalent
keywords: Ca2+ channel; End-to-side neurorrhaphy; Nerve regeneration; TOF–SIMS