An immunocytochemical study of mitochondrial manganese-superoxide dismutase in the rat hippocampus after kainate administration.
We examined the immunocytochemical distribution of mitochondrial Mn-superoxide dismutase (SOD-2) in the rat hippocampus after systemic injection of kainic acid (KA), in order to understand SOD-2-responsible antioxidant defense mechanism during the neurodegenerative process. SOD-2 immunostaining was more intense in CA3 pyramidal neurons than in CA1 neurons in the normal hippocampus. The immunoreactivity in region CA1 was reduced without significant neuronal losses within 12 h of KA injection. The CA1 and CA3 neurons lost their immunoreactivity, whereas SOD-2-positive glia-like cells proliferated, mainly throughout the CA1 sector, and had intense immunoreactivity 3 and 7 days after KA injection. This immunocytochemical distribution of SOD-2-positive non-neuronal elements was similar to that of glial fibrillary acidic protein (GFAP) and S-100 protein-positive cells. Activated microglial cells selectively marked with lectin occurred in the areas affected by the KA-induced lesion. Double-labeling immunocytochemistry showed the co-localization of SOD-2-positive non-neuronal cells and GFAP or S-100 protein-like immunoreactivity in the same cells. This suggests that astroglial cells mobilized to synthesize of SOD-2 protein in a response to KA toxicity designed to reduce the oxidative damage.
Kim
H C
HC
Section of Pharmacology and Toxicology, Department of Pharmacy, Kangwon National University, Korea Institute of Drug Abuse, Chunchon, South Korea. kimhc@cc.kangwon.ac.kr
Jhoo
W K
WK
Kim
W K
WK
Suh
J H
JH
Shin
E J
EJ
Kato
K
K
Ho Ko
K
K
D000818:Animals; D005904:Glial Fibrillary Acidic Protein / Q000032:analysis; D006624:Hippocampus / Q000166:cytology / Q000187:drug effects* / Q000201:enzymology; D007150:Immunohistochemistry; D007608:Kainic Acid / Q000494:pharmacology*; D008297:Male; D008928:Mitochondria / Q000201:enzymology*; D009474:Neurons / Q000737:chemistry / Q000187:drug effects / Q000201:enzymology; D051381:Rats; D017207:Rats, Sprague-Dawley; D009418:S100 Proteins / Q000032:analysis; D013482:Superoxide Dismutase / Q000378:metabolism*
D005904:Glial Fibrillary Acidic Protein; D009418:S100 Proteins; D013482:Superoxide Dismutase; D007608:Kainic Acid