Expression of MCP-1 in the hippocampus of SHRSP with ischemia-related delayed neuronal death.
1. The expression of monocyte chemoattractant protein-1 (MCP-1) was examined in stroke-prone spontaneously hypertensive rats with transient global ischemia in order to study the involvement of the infiltration of blood monocytes in the mechanism of ischemia-related neuronal death. 2. The brains of the animals with occlusion of the bilateral carotid arteries for 10 min were removed at 8 h, 1, 2, 4 and 7 days after reperfusion. Frozen sections were used for in situ hybridization and tissue specimens from the hippocampus and the cerebral cortex were used to measure the concentration of MCP-1 by ELISA. 3. No MCP-1 mRNA was detected in the hippocampus of the sham group animals. One day after ischemia-reperfusion, MCP-1 mRNA was clearly expressed in the CA4 subfield and the molecular layer of the dentate gyrus, while it was slightly expressed in the lacnosum moleculare of the CA1 subfield. A dramatic expression was demonstrated in the entire CA1 subfield at 2 days after the operation. Most of the cells expressing MCP-1 were astrocytes. At 4 and 7 days after reperfusion, no MCP-1 mRNA was detected in the hippocampus. The concentration of MCP-1 protein dramatically increased in the hippocampus at 2 days after reperfusion. 4. Taken together with the findings of our previous study showing an increased permeability of the blood-brain barrier in the hippocampus from 12 h after ischemia-reperfusion, the astrocytes expressing MCP-1 might therefore induce the migration of monocytes into the brain parenchyma. As a result, such astrocytes expressing MCP-1 may therefore be related to the pathological events of delayed neuronal death in the pyramidal neurons.
Sakurai-Yamashita
Yasuko
Y
Department of Pharmacology, Nagasaki University Graduate School of Biomedical Sciences, Nagasaki, 852-8523, Japan. yasukosy@net.nagasaki-u.ac.jp
Shigematsu
Kazuto
K
Yamashita
Kimihiro
K
Niwa
Masami
M
D000818:Animals; D002545:Brain Ischemia / Q000378:metabolism / Q000473:pathology*; D017536:Carotid Artery, Common / Q000473:pathology; D016923:Cell Death; D018932:Chemokine CCL2 / Q000378:metabolism*; D006624:Hippocampus / Q000098:blood supply / Q000378:metabolism* / Q000473:pathology; D008297:Male; D009474:Neurons / Q000378:metabolism / Q000473:pathology* / Q000502:physiology; D051381:Rats; D011918:Rats, Inbred SHR; D020521:Stroke / Q000150:complications / Q000378:metabolism
C491766:Ccl2 protein, rat; D018932:Chemokine CCL2