Upregulated and prolonged differentiation potential of the ependymal cells lining the ventriculus terminalis in human fetuses.
The ventriculus terminalis (VT) is a dilated cavity within the conus medullaris of the spinal cord. Although the VT was discovered in the mid-nineteenth century, little is known about its characteristics during development in human fetuses. Ependymal cells lining the cavities within the CNS retain high differentiation potential, and are believed to be responsible for the postnatal neurogenesis. To evaluate the differentiation capacity of the ependymal cells lining the VT during development, we examined glial fibrillary acidic protein (GFAP) and proliferating cell nuclear antigen (PCNA) expression in the spinal cord of 18-24-week-old human fetuses. GFAP is a marker for the degree of ependymal cell differentiation in the human fetus, and PCNA is a well-known marker for cell division. Morphological characteristics of the VT were also examined. At the lower portion of the conus medullaris, the central canal abruptly expands dorsally to become the VT. Then the VT widens bilaterally while its anteroposterior diameter reduces gradually in a caudal direction. Finally, the VT becomes a narrow, transverse slit at the level of the lowermost conus medullaris. Compared with those lining the central canal, more numerous ependymal cells lining the VT showed more intensive GFAP and PCNA expression throughout all gestational ages examined. This suggests that, in the developing human spinal cord, ependymal cells lining the VT retain their differentiation potential, including a higher proliferative capacity, until a later stage of development than those lining the central canal.
Song
Dae Yong
DY
Department of Anatomy and Institute of Basic Medical Science, Yonsei University Wonju College of Medicine, Ilsan-Dong 162, Wonju, Kangwon-Do 220-701, Republic of Korea.
Cho
Byung Pil
BP
Choi
Byoung Young
BY
Yang
Young Chul
YC
Lee
Bong Hee
BH
Lim
Chang Kyo
CK
Kang
Ho Suck
HS
D037881:Aborted Fetus / Q000033:anatomy & histology / Q000502:physiology*; D015415:Biomarkers; D002454:Cell Differentiation / Q000502:physiology; D049109:Cell Proliferation; D004805:Ependyma / Q000166:cytology / Q000196:embryology* / Q000502:physiology*; D004847:Epithelial Cells / Q000166:cytology / Q000502:physiology*; D005260:Female; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D006801:Humans; D009473:Neuronal Plasticity / Q000502:physiology; D011247:Pregnancy; D018809:Proliferating Cell Nuclear Antigen / Q000378:metabolism; D013116:Spinal Cord / Q000166:cytology / Q000196:embryology* / Q000502:physiology*; D013234:Stem Cells / Q000166:cytology / Q000502:physiology; D015854:Up-Regulation / Q000502:physiology
D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein; D018809:Proliferating Cell Nuclear Antigen