Methylazoxymethanol acetate ablation of mouse cerebellar granule cells: Effects on synaptic neurochemistry

Mice whose cerebella were rendered granuloprival by neonatal injection of methylazoxymethanol had decreased cerebellar adult levels of glutamic acid (GA) (-29%), decreased GA presynaptic uptake (-45%) and increased GA postsynaptic binding (+65%) compared to controls, suggesting that GA is the neurotransmitter of cerebellar granule cells. Total binding for the β-adrenergic receptor, the muscarinic cholinergic receptor and the kainic acid receptor fell commensurate with the degree of cerebellar hypoplasia. In contrast, increases in glutamic acid decarboxylase (+59%), γ-aminobutyric acid (GABA) uptake (+52%), and endogenous GABA levels (+29%) and a decrease in GABA binding (-32%) favor GABA as the neurotransmitter of other cerebellar interneurons.