Induction of heme oxygenase-1 (HO-1) in the contused spinal cord of the rat.
The induction of heme oxygenase-1 (HO-1) was studied in intact spinal cords and injured spinal cords after a moderate, thoracic contusion injury. HO-1 was immunolocalized in the normal cord and along the axis of the cord at 1, 2, 3 and 4 days after contusion. Induction of this enzyme in astrocytes and microglia/macrophages was evaluated using immunofluorescent double labeling with monoclonal antibodies to HO-1 and either glial fibrillary acidic protein or the complement C3bi receptor. HO-1 was expressed in neurons in the normal spinal cord. After contusion, HO-1 was induced in both gray and white matter at the impact site. In segments of cord that were 1 cm proximal or distal to the injury, HO-1 was primarily induced in the dorsal columns and occasionally in the lateral white matter. This pattern of induction was noted at all time points. The HO-1 was induced primarily in microglia/macrophages. The distribution of the HO-1 positive cells closely correlated with the pattern of intraparenchymal hemorrhage. These findings demonstrate acute induction of HO-1 in non-neuronal cells in the injured spinal cord. Induction of HO-1 in glia may be a consequence of multiple factors including exposure to heme proteins, hypoxia and oxidative stress.
Mautes
A E
AE
Department of Neurosurgery, University of California, San Francisco, CA 94143-0520, USA.
Kim
D H
DH
Sharp
F R
FR
Panter
S
S
Sato
M
M
Maida
N
N
Bergeron
M
M
Guenther
K
K
Noble
L J
LJ
D000818:Animals; D015153:Blotting, Western; D003288:Contusions / Q000201:enzymology*; D004789:Enzyme Activation / Q000502:physiology; D005455:Fluorescent Antibody Technique; D006419:Heme Oxygenase (Decyclizing) / Q000032:analysis / Q000096:biosynthesis*; D051547:Heme Oxygenase-1; D008264:Macrophages / Q000502:physiology; D008297:Male; D017628:Microglia / Q000502:physiology; D051381:Rats; D017207:Rats, Sprague-Dawley; D013116:Spinal Cord / Q000098:blood supply / Q000166:cytology / Q000201:enzymology; D013119:Spinal Cord Injuries / Q000201:enzymology* / Q000276:immunology
D006419:Heme Oxygenase (Decyclizing); D051547:Heme Oxygenase-1