Endoplasmic reticulum (ER) stress protein responses in relation to spatio-temporal dynamics of astroglial responses to status epilepticus in rats.
In the present study, we investigated whether endoplasmic reticulum (ER) stress is associated with neuronal- and astroglial-death in the hippocampus using LiCl-pilocarpine-induced status epilepticus (SE) rat model. Glucose-related protein (GRP) 78 and protein disulfide isomerase (PDI) expressions were transiently increased in CA1 neurons and dentate granule cells, and subsequently decreased in these cells following SE. GRP94 and calnexin (CNX) expression was gradually reduced in CA1 neurons, not in dentate granule cells. Phospho-protein kinase RNA (PKR)-like ER kinase (pPERK), phospho-eukaryotic initiation factor 2α (peIF2A) and CCAAT/enhancer-binding protein homologous protein (CHOP) immunoreactivities were observed in 17%, 12% and 7% of degenerating CA1 neurons, respectively. GRP 78 and PDI expressions were also up-regulated in reactive astrocytes within the CA1-3 regions. In the molecular layer of the dentate gyrus, PDI-positive astrocytes showed TUNEL signal, nuclear apoptosis inducing factor translocation and pPERK/peIF2A/CHOP immunoreactivities. Four weeks after SE, clasmatodendritic astrocytes showed pPERK peIF2A and CNX immunoreactivities without CHOP expression. These findings indicate that SE-induced ER stress may be associated with astroglial apoptosis and autophagic astroglial death in the regional-specific pattern.
Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon, Kangwon-Do 200-702, South Korea.
A-R
AR
Ko
Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon, Kangwon-Do 200-702, South Korea.
J Y
JY
Kim
Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon, Kangwon-Do 200-702, South Korea.
H-W
HW
Hyun
Department of Anatomy and Neurobiology, College of Medicine, Hallym University, Chuncheon, Kangwon-Do 200-702, South Korea. Electronic address: jieunkim@hallym.ac.kr.
J-E
JE
Kim
D000818:Animals; D051033:Apoptosis Inducing Factor / Q000378:metabolism; D001253:Astrocytes / Q000378:metabolism*; D037281:Calnexin / Q000378:metabolism; D004195:Disease Models, Animal; D000091342:Endoplasmic Reticulum Chaperone BiP; D059865:Endoplasmic Reticulum Stress / Q000502:physiology*; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism; D006624:Hippocampus / Q000473:pathology*; D020287:In Situ Nick-End Labeling; D018021:Lithium Chloride / Q000633:toxicity; D008297:Male; D008565:Membrane Proteins / Q000378:metabolism; D009419:Nerve Tissue Proteins / Q000378:metabolism; D010862:Pilocarpine; D051381:Rats; D017207:Rats, Sprague-Dawley; D013226:Status Epilepticus / Q000139:chemically induced / Q000473:pathology*; D013997:Time Factors; D051742:Transcription Factor CHOP / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects / Q000502:physiology
C494831:Aifm1 protein, rat; D051033:Apoptosis Inducing Factor; C497250:Ddit3 protein, mouse; D000091342:Endoplasmic Reticulum Chaperone BiP; D018840:HSP70 Heat-Shock Proteins; C000717248:Hspa5 protein, mouse; D008565:Membrane Proteins; D009419:Nerve Tissue Proteins; C018551:glucose-regulated proteins; D010862:Pilocarpine; D037281:Calnexin; D051742:Transcription Factor CHOP; D018021:Lithium Chloride
GRP78; GRP94; calnexin; protein disulfide isomerase; status epilepticus