Purchase this article with an account.
ES Yamada, DW Marshak; Wide-field Ganglion Cell Types in the Macaque Retina . Invest. Ophthalmol. Vis. Sci. 2002;43(13):2776.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Purpose: To identify wide-field retinal ganglion cells in the macaque retina based on their dendritic morphology and pattern of stratification in the inner plexiform layer (IPL). Methods: Eyes were obtained from 8 adult Macaca mulatta shortly after death, and retinal ganglion cells were intracellularly injected with Neurobiotin using an in vitro retinal preparation. The retinas were also labeled with antibodies to choline acetyltransferase (ChAT), calbindin (CB) or tyrosine-hydroxylase (TH). The depth of dendritic stratification was defined in relation to these markers by using a confocal microscope. Results: From a total of 82 injected retinal ganglion cells, we identified 18 parasol cells, 11 midget cells, 11 small-bistratified cells and 43 wide-field (WF) ganglion cells. All WF ganglion cells had dendritic trees at least twice as wide as parasol cells from the same eccentricity. Based on the dendritic tree branching pattern we classified WF ganglion cells in 14 different types, all of which could be grouped in 4 major categories according to the pattern and depth of dendritic stratification in the IPL: narrowly-unistratified (8 types), broadly-unistratified (3 types), partially-bistratified (1 type) and diffuse (2 types). Most cell types could be correlated to ganglion cells previously described in other mammals. In the monkey, among the identified cell types there were cells very similar to cat alpha, delta, epsilon and gamma ganglion cells regarding both the dendritic morphology and stratification depth. Cell types with dendritic morphology similar to cat zeta and theta ganglion cells were also identified, but there were differences in stratification depth. A cell type stratifying in sublamina b of the IPL and making frequent contacts with dendrites of ON-cholinergic amacrine cells is a good candidate, in this regard, for an ON-direction selective ganglion cell in the monkey retina; however, its dendritic morphology differs from rabbit's ON-DS cell. A partially-bistratified cell type had branches ramifying at S2 and the inner tree at S5 and, therefore, it is a good candidate to receive inputs from blue cone bipolar cell axons. Conclusion: The diversity of morphological types of retinal ganglion cells observed in the macaque retina indicates that there are many functional cell types yet to be characterized.
This PDF is available to Subscribers Only