Amacrine cells in the primate retina
Final Report Abstract
In some mammalian retinas, the calcium binding protein calretinin is expressed by a variety of neurones including the AII amacrine cell, a crucial neuron in the rod pathway. We characterized the calretinin expressing neurones in human retina. Post mortem donor eyes were obtained with consent from the Lions’ NSW Eye Bank. Vertical Vibratome sections were cut along the horizontal meridian and processed for calretinin immunofluorescence. Other pieces of retina were pre-labelled with antibodies specific for calretinin and subsequently immunopositive cells were injected with the lipophilic dye Dil. Calretinin immunoreactive cells were located in the inner nuclear layer (INL) or in the ganglion cell layer (GCL). A total of 87 Dil labeled cells (27 in INL, 60 in GCL) was analysed. Most of the cells in the INL (23/27, 85%) had AII type morphology. In addition, we identified a wide-field amacrine cell type (n = 16) with semilunar type morphology as described. These cells were located either in the INL (n = 4) or in the GCL (n = 12). Nine of the DiI injected cells in the GCL resembled the G17 ganglion cell. Most of the other injected cells in the GCL had large dendritic fields and lacked axons suggesting that they are were wide-field amacrine cells (stellate-varicose type, n=26, or thorny type, n=5). Antibodies to calretinin can be used to identify AII and other amacrine cells in the human retina, enabling quantitative analysis of these cell types. For the quantitative analysis of interneurons in the marmoset retina we found that All amacrine cells account for the majority of calretinin (CaR) positive cells in the inner nuclear layer. Calbindin (CaBP) positive cells most likely include All cells, whereas parvalbumin (PV) positive cells form a separate population. Importantly, all our data conclude that bipolar and amacrine cell fractions remain stable across the retina. This is an interesting finding considering the fact that the retina contains a fovea, a region specialized on high acuity vision.
Publications
- Characterization Of Calretinin Immunoreactive Cells in the Human Retina. Abstract at the Australasian Neuroscience Society Annual Meeting 2014
Weltzien, Felix, Lee, S., Denkhaus, C, Martin, P. and Grünert, U.
