Chronological changes of N-methyl-D-aspartate receptors and excitatory amino acid carrier 1 immunoreactivities in CA1 area and subiculum after transient forebrain ischemia.
We investigated changes of immunoreactivities of N-methyl-D-aspartate receptor (NR) and of excitatory amino acid carrier 1 (EAAC-1), the neuronal glutamate transporter, in the vulnerable CA1 area and the less vulnerable subiculum of the gerbil hippocampus at various times following transient forebrain ischemia. At 30 min after ischemia-reperfusion, the intensity of NR immunoreactivity increased markedly in neurons of CA1 and subiculum, particularly NR2A/B, while EAAC-1 immunoreactivity was reduced in CA1. At 3 hr after reperfusion, the density of NR1 immunoreactivity markedly decreased in CA1. In contrast EAAC-1 immunoreactivity increased in CA1 and in the subiculum. At 12 hr after reperfusion, the decrease of NR1 immunoreactivity was not detected whereas EAAC-1 immunoreactivities in the CA1 area were intensified. In the subiculum, both NR subunits immunoreactivities decreased significantly, in contrast to the maintenance of EAAC-1 immunoreactivity. At 24 hr after reperfusion, both NR2A/B and EAAC-1 immunoreactivities decreased markedly in CA1 and subiculum. We tentatively suggest that the increase of NR immunoreactivity in CA1 at early times after ischemia-reperfusion may increase the delayed neuronal death, and that the increase or maintenance of EAAC-1 immunoreactivity at early times after ischemia-reperfusion may be an important factor in survival of neurons.
Kang
T C
TC
Department of Anatomy, College of Medicine, Hallym University, Chunchon, Kangwon-Do, 200-702, South Korea.
Hwang
I K
IK
Park
S K
SK
An
S J
SJ
Yoon
D K
DK
Moon
S M
SM
Lee
Y B
YB
Sohn
H S
HS
Cho
S S
SS
Won
M H
MH
D027322:Amino Acid Transport System X-AG / Q000378:metabolism*; D000818:Animals; D016923:Cell Death / Q000502:physiology*; D018891:Dentate Gyrus / Q000378:metabolism / Q000503:physiopathology; D005849:Gerbillinae; D050491:Glutamate Plasma Membrane Transport Proteins; D018698:Glutamic Acid / Q000378:metabolism; D006624:Hippocampus / Q000378:metabolism* / Q000503:physiopathology; D007150:Immunohistochemistry; D002546:Ischemic Attack, Transient / Q000378:metabolism* / Q000503:physiopathology; D008297:Male; D009474:Neurons / Q000378:metabolism; D011930:Reaction Time / Q000502:physiology*; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D015427:Reperfusion Injury / Q000378:metabolism* / Q000503:physiopathology; D027981:Symporters / Q000378:metabolism*; D013569:Synapses / Q000378:metabolism; D009435:Synaptic Transmission / Q000502:physiology; D013997:Time Factors
D027322:Amino Acid Transport System X-AG; D050491:Glutamate Plasma Membrane Transport Proteins; C409466:NR1 NMDA receptor; C120997:NR2A NMDA receptor; D016194:Receptors, N-Methyl-D-Aspartate; D027981:Symporters; D018698:Glutamic Acid