Subcellular localization of the alpha(7) nicotinic receptor in rat cerebellar granule cell layer

The distribution of the alpha(7) nicotinic receptor subunit in the rat cerebellum was studied immunohistochemically at the electron microscope level using an alpha(7) subunit-specific antibody. The granule cell layer showed a much lower level of immunoreactivity for the alpha(7) subunit than the Purkinje cell layer. Granule cell somata were completely devoid of labeling; this appeared to be restricted to glomeruli exclusively located in the membranes of granule cell dendrites. The alpha(7) immunolabeling was located not at active synaptic areas but was mostly perisynaptic. This localization suggests that nicotinic receptors containing the alpha(7) subunit could have a modulatory function and/or play a direct role in the generation of synaptic currents.