Muscarinic cholinergic receptors in the rat deep cerebellar nuclei: a quantitative autoradiographic study

The distribution of muscarinic cholinergic receptors within the rat deep cerebellar nuclei was analyzed using in vitro receptor binding of [3H]quinuclidinylbenzilate (QNB) in conjunction with autoradiography. The highest density of QNB binding sites occurred in the lateral cerebellar (dentate) nucleus. Interpositus nuclei displayed an intermediate density of muscarinic cholinergic binding sites with the posterior interpositus nucleus demonstrating higher binding than the anterior nucleus. The fastigial (medial) cerebellar nucleus exhibited the lowest levels of QNB binding among the four cerebellar nuclei. These results indicate that muscarinic cholinergic receptors are present in the deep cerebellar nuclei and that differences in receptor density occur among the four nuclear groups.