Cerebellar granule cells cultured from adolescent rats express functional NMDA receptors: an in vitro model for studying the developing cerebellum.
In the developing rat cerebellum functional NMDA receptors (NMDARs) expressing the NR2C subunit have been identified on or after postnatal day 19. We obtained primary cultured cells from 19- to 35-day-old rat cerebellum that expressed few oligodendrocytes or astrocytes. Cultured cells were immunoreactive for neuron-specific proteins thus indicating a neuronal population. The primary neuron present was the granule cell as indicated by immunofluorescence for the GABA(A) alpha 6 subunit. Whole-cell patch-clamp experiments indicated that functional NMDARs were present. Functional characteristics of NMDARs expressed in cerebellar granule cells (CGCs) obtained from adolescent animals were similar to those previously reported for NMDARs expressed in CGCs obtained from neonatal rats. Cultured CGCs obtained from older animals contained NMDARs that were inhibited by EtOH and were less sensitive to the NR2B subunit-specific antagonist Ro 25-6981. Furthermore, NMDA-induced currents were smaller than those observed in CGCs. Western blot analysis indicated the presence of the NMDA NR2A and NR2C subunits, but not the NR2B in cultures obtained from the adolescent rats. CGCs obtained from adolescent rats express functional NMDARs consistent with a developmental profile observed in vivo.
Popp
R Lisa
RL
Department of Pharmacology and Neuroscience, and South Plains Alcohol and Addiction Center, Texas Tech University Health Sciences Center, Lubbock, Texas, USA. lisa.popp@TTUHSC.edu
Reneau
Jason C
JC
Dertien
Janet S
JS
D000367:Age Factors; D000818:Animals; D000831:Animals, Newborn; D002478:Cells, Cultured; D002492:Central Nervous System Depressants / Q000494:pharmacology; D002531:Cerebellum / Q000166:cytology*; D000431:Ethanol / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D008297:Male; D008564:Membrane Potentials / Q000187:drug effects / Q000528:radiation effects; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009474:Neurons / Q000378:metabolism*; D018408:Patch-Clamp Techniques / Q000379:methods; D010636:Phenols / Q000494:pharmacology; D010880:Piperidines / Q000494:pharmacology; D051381:Rats; D017207:Rats, Sprague-Dawley; D011963:Receptors, GABA-A / Q000235:genetics / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*; D013997:Time Factors
D002492:Central Nervous System Depressants; D018691:Excitatory Amino Acid Antagonists; C546173:Gabra6 protein, rat; D009419:Nerve Tissue Proteins; D010636:Phenols; D010880:Piperidines; D011963:Receptors, GABA-A; D016194:Receptors, N-Methyl-D-Aspartate; C109643:Ro 25-6981; D000431:Ethanol