Retrograde transport of radioactivity along axons of ascending cerebellar pathways after injection of N-[3H]acetyl-D-mannosamine into the mesencephalon of the rat.
Either the sialic acid precursor N-[3H]acetyl-D-mannosamine ([3H]ManNAc) or horseradish peroxidase (HRP) or both were injected into the mesencephalon of 15 rats. Localisation of radioactivity was performed by light microscopic autoradiography and HRP was histochemically localised with 3,3'-diaminobenzidine. After injection of either [3H]ManNAc or HRP, cell bodies in the central cerebellar nuclei were filled with radioactivity or HRP respectively. The distribution over contra- and ipsilateral interposed, dentate and fastigial nuclei of [3H]ManNAc-labelled and HRP-labelled cells is similar for both types of labelling. Since HRP is known to be transported retrogradely, a similar localisation of radioactivity-accumulating cells and HRP-filled cell bodies in the central cerebellar nuclei, lead us to the conclusion that radioactively-labelled ManNAc or its derivatives are also retrogradely transported in this system. There seem to be two possibilities for label uptake in afferents axons: (1) the uptake into axons which are disrupted by the injection needle and (2) the uptake by intact nerve endings or axons. After injection of [3H]ManNAc, the neuropil of central cerebellar nuclei shows a higher concentration of silver grains than the labelled cell bodies. This could be due to labelled dendrites caused by retrograde transport.
D000344:Afferent Pathways / Q000378:metabolism; D000818:Animals; D001345:Autoradiography; D001370:Axonal Transport; D002529:Cerebellar Nuclei / Q000378:metabolism*; D004292:Dominance, Cerebral / Q000502:physiology; D005557:Formaldehyde / Q000378:metabolism; D006595:Hexosamines / Q000378:metabolism*; D006735:Horseradish Peroxidase; D008297:Male; D008636:Mesencephalon / Q000378:metabolism*; D051381:Rats; D012012:Red Nucleus / Q000378:metabolism; D012154:Reticular Formation / Q000378:metabolism; D012794:Sialic Acids / Q000378:metabolism; D014316:Tritium
D006595:Hexosamines; D012794:Sialic Acids; D014316:Tritium; D005557:Formaldehyde; D006735:Horseradish Peroxidase; C002022:N-acetylmannosamine