Limited differentiation to neurons and astroglia from neural stem cells in the cortex and striatum after ischemia/hypoxia in the neonatal rat brain.
OBJECTIVE
We examined whether progenitor neural stem cells can differentiate successfully into mature neurons and astrocytes in a rat model of neonatal hypoxic-ischemic encephalopathy.


METHODS
Seven-day-old Wistar rats were subjected to hypoxic-ischemic stress. At days 5 to 7 after hypoxic-ischemic stress, 5-bromodeoxyuridine (an early marker of cell proliferation) was injected, and the brains were retrieved at 14, 28, and 42 days after hypoxic-ischemic stress. Immunohistochemical and immunofluorescent studies were carried out for 5-bromodeoxyuridine, neuronal nuclear antigen (a marker protein of matured neuron), and glial fibrillary acidic protein (a protein marker of mature astrocytes).


RESULTS
Only 1% of neuronal nuclear antigen-positive and 4.6% of glial fibrillary acidic protein-positive cells could be detected among the 5-bromodeoxyuridine-immunopositive cells in the peri-infarcted area of the cortex and the striatum, respectively, at 14 days after hypoxic-ischemic stress. There were no such double-staining cells at 28 and 42 days after hypoxic-ischemic stress.


CONCLUSIONS
The intrinsic ability for neurologic self-repair was limited at the maturation step after hypoxic-ischemic stress in the neonatal rat brain.
Ikeda
Tomoaki
T
Department of Obstetrics and Gynecology, Miyazaki Medical College, University of Miyazaki, Miyazaki, Japan. tikeda44@hotmail.com
Iwai
Masanori
M
Hayashi
Takeshi
T
Nagano
Isao
I
Shogi
Mikio
M
Ikenoue
Tsuyomu
T
Abe
Koji
K
D000818:Animals; D034961:Antigens, Nuclear / Q000378:metabolism; D000963:Antimetabolites / Q000378:metabolism; D001253:Astrocytes / Q000166:cytology*; D002545:Brain Ischemia / Q000503:physiopathology*; D001973:Bromodeoxyuridine / Q000378:metabolism; D002454:Cell Differentiation / Q000502:physiology*; D002540:Cerebral Cortex; D003342:Corpus Striatum / Q000378:metabolism; D004195:Disease Models, Animal; D005904:Glial Fibrillary Acidic Protein / Q000378:metabolism; D007150:Immunohistochemistry; D009474:Neurons / Q000166:cytology*; D051381:Rats; D017208:Rats, Wistar; D013234:Stem Cells / Q000502:physiology*
D034961:Antigens, Nuclear; D000963:Antimetabolites; D005904:Glial Fibrillary Acidic Protein; D001973:Bromodeoxyuridine