Neuronal and glial structures of the superficial layers of the human superior colliculus.

We studied neuronal and glial elements in the superficial layers of the human superior colliculus by means of Nissl stains, Golgi impregnations, histochemical demonstration of NADPH-d activity and immunohistochemistry for glial fibrillary acidic protein (GFAP) in astrocytes. The glia-neuron interface was visualized with Wisteria floribunda agglutinin (WFA), which is a marker for perineuronal nets. The laminar pattern and the morphology of the major cell types closely resembled that found in other species although the thickness of the stratum zonale varied and the diversity of interneurons was greater than in other mammals. Furthermore, the stratum griseum superficiale showed a characteristic clustering of cells, the surfaces of which were intensely labeled by WFA. The clusters disappeared when GFAP expression increased.