title: Unfolded protein response is activated in the ipsilateral thalamus following focal cerebral infarction in hypertensive rats.
abstract: Focal cerebral cortical infarction causes secondary neurodegeneration in the remote regions, such as the ventroposterior nucleus of the thalamus. Retrograde degeneration of thalamocortical fibers is considered as the principle mechanism, but the exact molecular events remain to be elucidated. This study aimed to investigate whether unfolded protein response (UPR) is activated in thalamic neurons following distal middle cerebral artery occlusion (MCAO) in stroke-prone renovascular hypertensive rats. Immunostaining and immunoblotting were performed to evaluate the expression of Grp78 and its downstream effectors in the thalamus at 3, 7 and 14 days after MCAO. Secondary thalamic degeneration was assessed with Nissl staining and NeuN immunostaining. Neuronal death was not apparent at 3 days post-ischaemia but was evident in the thalamus at 7 and 14 days after MCAO. Grp78 level was reduced in the ipsilateral thalamus at 3 and 7 days after MCAO. In parallel, phosphorylated eIF2α and ATF4 levels were elevated, indicating the activation of UPR. In contrast, ATF6α and CHOP levels were not changed. These results suggest that UPR is activated before neuronal death in the ipsilateral thalamus after MCAO and may represent a key early event in the secondary thalamic degeneration.
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Jian
authors: J
authors: Zhang
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Hongbing
authors: H
authors: Chen
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Weixian
authors: W
authors: Huang
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Chunyan
authors: C
authors: Zhou
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Jingjing
authors: J
authors: Li
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Shihui
authors: S
authors: Xing
authors: Department of Neurology, First Affiliated Hospital, Guangxi Medical University, Nanning, China.
authors: Li
authors: L
authors: Chen
authors: Department of Neurology, Guangzhou No. 8 People's Hospital, Guangzhou Medical University, Guangzhou, China.
authors: Chuo
authors: C
authors: Li
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Chao
authors: C
authors: Dang
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Gang
authors: G
authors: Liu
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Zhong
authors: Z
authors: Pei
authors: Department of Neurology and Stroke Center, First Affiliated Hospital, Sun Yat-Sen University, Guangzhou, China.
authors: Jinsheng
authors: J
authors: Zeng
mesh_terms: D000818:Animals; D002544:Cerebral Infarction / Q000378:metabolism* / Q000473:pathology; D006973:Hypertension / Q000378:metabolism* / Q000473:pathology; D008297:Male; D051381:Rats; D017207:Rats, Sprague-Dawley; D013788:Thalamus / Q000378:metabolism* / Q000473:pathology; D056811:Unfolded Protein Response / Q000502:physiology*
keywords: cerebral infarction; endoplasmic reticulum stress; glucose-regulated protein 78; thalamus; unfolded protein response