title: Uniform distribution and similar turnover rates of individual gangliosides along axons of retinal ganglion cells in the chicken.
abstract: In 5-month-old chickens, an intracranial injection of N-[3H]acetylmannosamine led to a labeling of all optic lobe ganglioside species in a fashion paralleling the relative ganglioside distribution. In contrast, after an intraocular injection of the same precursor, the optic nerve and the optic lobe connected to the injected eye, possessed an exceptionally high labelling of GD1a (in comparison with GD1a-sialic acid), and only negligible incorporation of radioactivity into the myelin-specific GM4 and into a fraction migrating close to GM1. Subtracting both these very low labelling fractions from the total gave a percentage distribution of ganglioside sialic acid which now corresponded well to the distribution of radioactivity along the whole optic nerve, including the region of nerve terminals in the optic lobe. This pattern of ganglioside labelling, which indicates that GD1a carries about 60% of total ganglioside sialic acid of retinal ganglion cell axons, did not change remarkably during post-hatching development up to 5 months. Long-time incorporation studies revealed similar turnover rates of the main retinal ganglion cell gangliosides. The average half-lives were 34 (GD1a), 35 (GQ1b), 36.3 (GT1b) and 38.5 days (GD3). The findings suggest that the retinal ganglion cell axons and their presynaptic terminals possess a similar ganglioside pattern, characterized by a high content of GD1a.
mesh_terms: D000375:Aging; D000818:Animals; D001370:Axonal Transport; D002645:Chickens; D005677:G(M1) Ganglioside / Q000378:metabolism; D005732:Gangliosides / Q000378:metabolism*; D009185:Myelin Proteins / Q000378:metabolism; D009474:Neurons / Q000378:metabolism; D012160:Retina / Q000378:metabolism*; D013477:Superior Colliculi / Q000378:metabolism; D014795:Visual Pathways / Q000378:metabolism
chemical_list: D005732:Gangliosides; D009185:Myelin Proteins; D005677:G(M1) Ganglioside; C028253:ganglioside, GM4