Identification and morphological classification of neuronal cell types within Astyanax mexicanus retina

<p>Photoreceptor, bipolar and amacrine cells in the retina of surface fish Astyanax mexicanus were morphologically characterized using DiOlistic techniques. In this method, DiI-coated microcarriers are applied at high speed onto the surfaces of retinal slices where DiI then delineates axons, somata and dendrites of isolated neurons. Three photoreceptors were identified: rods, single and double cones. Bipolar cells were separated into eleven morphological types: three Boff-types with axon boutons exclusively in sublamina a, four-Bon types with axon boutons exclusively in sublamina b and four multistratified types with axon boutons in both sublamina a and b. Amacrine cells were separated into thirteen morphological types: seven Aoff-types and six-Aon types. The information from this study can be used to compare the overall eye development and general changes in retinal structure, degrees of retinal degeneration and/or apoptotic loss of specific cell types between the ancestral Astyanax morphotype and the regressed cave forms.</p>