Patterned neuropathologic events occurring in hyh congenital hydrocephalic mutant mice.
Hyh mutant mice develop long-lasting hydrocephalus and represent a good model for investigating neuropathologic events associated with hydrocephalus. The study of their brains by use of lectin binding, bromodeoxyuridine labeling, immunochemistry, and scanning electron microscopy revealed that certain events related to hydrocephalus followed a well-defined pattern. A program of neuroepithelium/ependyma denudation was initiated at embryonic day 12 and terminated at the end of the second postnatal week. After the third postnatal week the denuded areas remained permanently devoid of ependyma. In contrast, a selective group of ependymal areas resisted denudation throughout the lifespan. Ependymal denudation triggered neighboring astrocytes to proliferate. These astrocytes expressed particular glial markers and formed a superficial cell layer replacing the lost ependyma. The loss of the neuroepithelium/ependyma layer at specific regions of the ventricular walls and at specific stages of brain development would explain the fact that only certain brain structures had abnormal development. Therefore, commissural axons forming the corpus callosum and the hippocampal commissure displayed abnormalities, whereas those forming the anterior and posterior commissures did not; and the brain cortex was not homogenously affected, with the cingular and frontal cortices being the most altered regions. All of these telencephalic alterations developed at stages when hydrocephalus was not yet patent at the lateral ventricles, indicating that abnormal neural development and hydrocephalus are linked at the etiologic level, rather than the former being a consequence of the latter. All evidence collected on hydrocephalic hyh mutant mice indicates that a primary alteration in the neuroepithelium/ependyma cell lineage triggers both hydrocephalus and abnormalities in telencephalic development.
Páez
Patricia
P
Departamento de Biología Celular, Genética y Fisiología, Facultad de Ciencias, Universidad de Málaga, Málaga, Spain.
Bátiz
Luis-Federico
LF
Roales-Buján
Ruth
R
Rodríguez-Pérez
Luis-Manuel
LM
Rodríguez
Sara
S
Jiménez
Antonio Jesús
AJ
Rodríguez
Esteban Martín
EM
Pérez-Fígares
José Manuel
JM
D000818:Animals; D000831:Animals, Newborn; D001921:Brain / Q000002:abnormalities* / Q000473:pathology* / Q000648:ultrastructure; D001973:Bromodeoxyuridine / Q000378:metabolism; D004195:Disease Models, Animal; D018450:Disease Progression; D004622:Embryo, Mammalian; D004805:Ependyma / Q000002:abnormalities / Q000473:pathology; D005260:Female; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology*; D006849:Hydrocephalus / Q000235:genetics / Q000473:pathology / Q000503:physiopathology; D008297:Male; D051379:Mice; D008817:Mice, Mutant Strains; D008840:Microfilament Proteins / Q000235:genetics*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D011247:Pregnancy
C481382:Hydin protein, mouse; D008840:Microfilament Proteins; D009419:Nerve Tissue Proteins; D001973:Bromodeoxyuridine