Morphological correlates of Y, X and W type ganglion cells in the cat's retina.
After physiological recordings with microelectrodes containing horseradish peroxidase (HRP), morphological properties of Y, X and W type ganglion cells were studied on flat-mounted cat's retinas. While all the Y cells (N = 9) and the X cells (N = 8) revealed alpha and beta cell morphologies of Boycott and Wässle [J. Physiol. 240, 397-419 (1974)], respectively, W cells (N = 4) revealed various morphological types including their gamma and delta cells. The Y cells were larger than X cells in soma diameter, but the W cells were of the same range as X cells. Electron microscopic observations of the cross-sectioned nerve fiber bundles provided evidence for the segregation of axon diameters into the three groups corresponding to Y, X and W axons. It was discussed that functional trichotomy of retinal ganglion cells is related to the differentiation more in axon diameter rather than in soma size.
D000200:Action Potentials; D000818:Animals; D001369:Axons / Q000648:ultrastructure; D001699:Biometry; D002415:Cats; D005071:Evoked Potentials; D008854:Microscopy, Electron; D009900:Optic Nerve / Q000648:ultrastructure; D012160:Retina / Q000648:ultrastructure*; D012165:Retinal Ganglion Cells / Q000502:physiology / Q000648:ultrastructure*