Abstract
The distribution and fine structure of [Met] -Enkephalin-Arg6-Gly7-Leu8-like immunoreactive (MEAGL-LI) neurons in the rat cerebellum were examined by light and electron microscopic immunohistochemistry. Immunoreactive neurons which were designated to be Golgi cells were found in the granular layer. These MEAGL-LI Golgi cells were distributed heterogeneously in the cerebellar cortex; the densest distribution was seen in the ventral and anterior vermis, moderate distribution in the pedunculofloccular lobe (PFL) and less in the dorsal and posterior parts of the cerebellar hemispheres. Immunoreactive Golgi cells showed well-developed organelles, such as rough-surfaced endoplasmic reticulum (r-ER) and Golgi complex as well as immunoreactive substances throughout the cytoplasm. On the surfaces of immunoreactive neurons non-immunoreactive axons made axo-somatic synapses. MEAGL-LI neuronal elements were distributed as components of the cerebellar glomeruli in the granular layer. Some of them were presynaptic axons which made axo-dendritic synapses with non-immunoreactive dendrites, and others were postsynaptic dendrites with which non-immunoreactive axons made axo-dendritic synapses. MEAGL-LI neuronal elements were also seen to make intimate contact with Purkinje cells in the Purkinje cell layer.
