Differential ontogenic pattern of metabotropic [3H]-L-glutamate receptors in normal and granule cell-deficient mouse cerebellum.
[3H]-L-glutamate binding site distribution corresponding to metabotropic receptors was studied by autoradiography during normal and altered cerebellar ontogeny in mice treated on postnatal days (PND) 5 and 6 with the antimitotic methylazoxymethanol (MAM). Quisqualate (QA)-induced and (2S,3S,4S)-alpha-(carboxycyclopropyl)-glycine (L-CCG-I)-induced [3H]-L-glutamate binding inhibition allowed us to distinguish between group I and group II metabotropic receptor binding sites. In control cerebellar cortex, the QA-sensitive binding site density increases during development, while the L-CCG-I-sensitive binding site density decreases. In the deep cerebellar nuclei (DCN), both populations of binding sites decrease during ontogeny. The antimitotic treatment induces: (1) a slight but significant increase in the QA-sensitive binding sites in the DCN at PND 10 and in the cerebellar cortex beginning from PND 20; (2) a retarded decrease in the L-CCG-I-sensitive metabotropic receptor binding site density. These differences could be due to a retarded cell maturation and/or an over-expression of some postsynaptic receptors in the adult cerebellum in response to the afference deficiency.
Becker
T
T
Laboratoire de Neurobiologie Cellulairé, Strasbourg, France.
Gombos
G
G
de Barry
J
J
D000600:Amino Acids, Dicarboxylic / Q000494:pharmacology; D000818:Animals; D001345:Autoradiography; D002529:Cerebellar Nuclei / Q000254:growth & development / Q000378:metabolism / Q000473:pathology; D002531:Cerebellum / Q000254:growth & development* / Q000378:metabolism / Q000473:pathology*; D003594:Cytoplasmic Granules / Q000502:physiology*; D018690:Excitatory Amino Acid Agonists / Q000494:pharmacology; D008746:Methylazoxymethanol Acetate / Q000031:analogs & derivatives / Q000633:toxicity; D051379:Mice; D008938:Mitosis / Q000187:drug effects; D016318:Quisqualic Acid / Q000494:pharmacology; D018094:Receptors, Metabotropic Glutamate / Q000187:drug effects / Q000378:metabolism*
D000600:Amino Acids, Dicarboxylic; D018690:Excitatory Amino Acid Agonists; D018094:Receptors, Metabotropic Glutamate; C035261:(alpha-carboxycyclopropyl)glycine; D008746:Methylazoxymethanol Acetate; D016318:Quisqualic Acid; C030667:methylazoxymethanol