Increased expression of glutamate transporters in subcortical white matter after transient focal cerebral ischemia.
Transient focal cerebral ischemia leads to extensive excitotoxic glial damage in the subcortical white matter. Efficient reuptake of released glutamate is essential for preventing glutamate receptor overstimulation and neuronal and glial death. The present study evaluates the expression of the main glutamate transporters (EAAT1, EAAT2, and EAAT3) in subcortical white matter of the rat after transient middle cerebral artery occlusion. Western blot analysis and immunohistochemistry show an increase in the expression of EAAT1 and EAAT2 in subcortical white matter early after ischemia which subsequently decreases at longer reperfusion periods. However, expression of both EAAT1 and EAAT2 remains higher in astrocytes forming the gliotic scar and in microglial/macrophage cells at the border of or within the infarct area, respectively. Taken together, these results indicate that there is a transient enhanced expression of EAATs in the subcortical white matter early after ischemia. Our findings reveal an adaptive response of subcortical white matter to increased levels of glutamate during focal cerebral ischemia which may limit excitotoxic damage.
Arranz
Amaia M
AM
CIBERNED and Departamento de Neurociencias, Universidad del País Vasco, 48940, Vizcaya, Spain.
Gottlieb
Miroslav
M
Pérez-Cerdá
Fernando
F
Matute
Carlos
C
D000818:Animals; D001253:Astrocytes / Q000378:metabolism / Q000473:pathology; D015153:Blotting, Western; D001921:Brain / Q000378:metabolism* / Q000473:pathology; D002545:Brain Ischemia / Q000378:metabolism / Q000473:pathology; D027341:Excitatory Amino Acid Transporter 1 / Q000378:metabolism*; D027342:Excitatory Amino Acid Transporter 2 / Q000378:metabolism*; D050580:Excitatory Amino Acid Transporter 3 / Q000378:metabolism*; D007150:Immunohistochemistry; D020244:Infarction, Middle Cerebral Artery / Q000378:metabolism* / Q000473:pathology; D008264:Macrophages / Q000378:metabolism / Q000473:pathology; D008297:Male; D017628:Microglia / Q000378:metabolism / Q000473:pathology; D009413:Nerve Fibers, Myelinated / Q000378:metabolism* / Q000473:pathology; D009460:Neurologic Examination; D051381:Rats; D017208:Rats, Wistar; D013997:Time Factors
D027341:Excitatory Amino Acid Transporter 1; D027342:Excitatory Amino Acid Transporter 2; D050580:Excitatory Amino Acid Transporter 3; C493398:Slc1a1 protein, rat; C493395:Slc1a2 protein, rat; C493392:Slc1a3 protein, rat