RT Journal Article
SR Electronic
T1 Developmental Changes in Diffusion Anisotropy Coincide with Immature Oligodendrocyte Progression and Maturation of Compound Action Potential
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 5988
OP 5997
DO 10.1523/JNEUROSCI.4983-04.2005
VO 25
IS 25
A1 Alexander Drobyshevsky
A1 Sheng-Kwei Song
A1 Georgi Gamkrelidze
A1 Alice M. Wyrwicz
A1 Matthew Derrick
A1 Fan Meng
A1 Limin Li
A1 Xinhai Ji
A1 Barbara Trommer
A1 Douglas J. Beardsley
A1 Ning Ling Luo
A1 Stephen A. Back
A1 Sidhartha Tan
YR 2005
UL http://www.jneurosci.org/content/25/25/5988.abstract
AB Disruption of oligodendrocyte lineage progression is implicated in the white-matter injury that occurs in cerebral palsy. We have previously published a model in rabbits consistent with cerebral palsy. Little is known of normal white-matter development in perinatal rabbits. Using a multidimensional approach, we defined the relationship of oligodendrocyte lineage progression and functional maturation of axons to structural development of selected cerebral white-matter tracts as determined by diffusion tensor imaging (DTI). Immunohistochemical studies showed that late oligodendrocyte progenitors appear at gestational age 22 [embryonic day 22 (E22)], whereas immature oligodendrocytes appear at E25, and both increase rapidly with time (∼13 cells/mm2/d) until the onset of myelination. Myelination began at postnatal day 5 (P5) (E36) in the internal capsule (IC) and at P11 in the medial corpus callosum (CC), as determined by localization of sodium channels and myelin basic protein. DTI of the CC and IC showed that fractional anisotropy (FA) increased rapidly between E25 and P1 (E32) (∼11% per day) and plateaued (<5% per day) after the onset of myelination. Postnatal maturation of the compound action potential (CAP) showed a developmental pattern similar to FA, with a rapid rise between E29 and P5 (in the CC, 18% per day) and a slower rise from P5 to P11 (in the CC, <5% per day). The development of immature oligodendrocytes after E29 coincides with changes in FA and CAP area in both the CC and IC. These findings suggest that developmental expansion of immature oligodendrocytes during the premyelination period may be important in defining structural and functional maturation of the white matter.