Lesion-induced changes in NMDA receptor subunit mRNA expression in rat visual cortex.
Focal lesions in the visual cortex are well known to induce pronounced perilesional reorganization of the neuronal circuitry. Since NMDA receptors crucially control synaptic plasticity and reorganization, we studied lesion-induced changes in their subunit expression and biophysical properties. Between 8 and 10 days after focal thermolesioning, pyramidal neurones in the near surround of the lesion were studied in acute brain slices. We found a significant decrease in the ratio of NR2A and NR2B subunit mRNA as compared to neurones from sham operated animals. Interestingly, no significant differences in the properties of NMDA receptor-mediated postsynaptic currents (NMDA PSCs) were observed between lesioned and sham operated animals. Thus, the observed perilesional changes in the NR2A/NR2B mRNA ratio appear to be subthreshold to result in significant changes in the functional properties of NMDA receptors.
Rumpel
S
S
Lehrstuhl für Zellphysiologie, Ruhr-Universität Bochum, Germany.
Hoffmann
H
H
Hatt
H
H
Gottmann
K
K
Mittmann
T
T
Eysel
U T
UT
D000818:Animals; D003714:Denervation / Q000009:adverse effects; D008564:Membrane Potentials / Q000187:drug effects / Q000502:physiology; D009416:Nerve Regeneration / Q000187:drug effects / Q000502:physiology*; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*; D017966:Pyramidal Cells / Q000166:cytology / Q000187:drug effects / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects / Q000235:genetics*; D014793:Visual Cortex / Q000166:cytology / Q000378:metabolism* / Q000601:surgery
C120997:NR2A NMDA receptor; C121001:NR2B NMDA receptor; D012333:RNA, Messenger; D016194:Receptors, N-Methyl-D-Aspartate