title: Sensory tract abnormality in the chick model of spina bifida.
abstract: Spina bifida aperta (SBA) is an open neural tube defect that occurs during the embryonic period. We created SBA chicks by incising the roof plate of the neural tube in the embryo. The area of the dorsal funiculus was smaller in the SBA chicks than in the normal controls. Additionally, the SBA group had fewer nerve fibres in the dorsal funiculus than the normal controls. The pathway of the ascending sensory nerves was revealed by tracing the degenerated nerve fibres using osmification. We cut the sciatic nerve (L5) of the control and SBA chicks at the central end of the dorsal root ganglion 1 day after hatching and fixed the tissue 3 days later. Degenerated sensory nerve fibres were observed in the ipsilateral dorsal funiculus in the control chicks. In contrast, degenerated sensory nerve fibres were observed in the ipsilateral and contralateral dorsal, ventral and lateral funiculi of the spinal cord in the SBA chicks. Consequently, fewer sensory nerve fibres ascended to the thoracic dorsal funiculus in the SBA chicks than in the normal controls. This is the first report of abnormal changes in the ascending sensory nerve fibres in SBA.
authors.affiliation: Department of Legal Medicine, Ehime University Graduate School of Medicine, Toon, Ehime, Japan.
authors.forename: Ryusuke
authors.initials: R
authors.lastname: Tsujimura
authors.forename: Katsumi
authors.initials: K
authors.lastname: Mominoki
authors.forename: Masae
authors.initials: M
authors.lastname: Kinutani
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Shimokawa
authors.forename: Takuya
authors.initials: T
authors.lastname: Doihara
authors.forename: Hiroaki
authors.initials: H
authors.lastname: Nabeka
authors.forename: Hiroyuki
authors.initials: H
authors.lastname: Wakisaka
authors.forename: Naoto
authors.initials: N
authors.lastname: Kobayashi
authors.forename: Seiji
authors.initials: S
authors.lastname: Matsuda
mesh_terms: D000344:Afferent Pathways / Q000002:abnormalities / Q000473:pathology / Q000503:physiopathology; D000818:Animals; D001369:Axons / Q000473:pathology*; D002642:Chick Embryo; D002645:Chickens; D004195:Disease Models, Animal; D020233:Gait Disorders, Neurologic / Q000209:etiology / Q000473:pathology / Q000503:physiopathology; D020439:Growth Cones / Q000473:pathology; D006614:Hindlimb / Q000294:innervation / Q000503:physiopathology; D019051:Rhizotomy / Q000379:methods; D011984:Sensory Receptor Cells / Q000473:pathology; D016137:Spina Bifida Cystica / Q000473:pathology* / Q000503:physiopathology; D013116:Spinal Cord / Q000002:abnormalities* / Q000473:pathology / Q000503:physiopathology; D013126:Spinal Nerve Roots / Q000473:pathology / Q000503:physiopathology / Q000601:surgery; D014855:Wallerian Degeneration / Q000209:etiology / Q000473:pathology* / Q000503:physiopathology