Aquino D A, Bisby M A, Ledeen R W
Neuroscience. 1987 Mar;20(3):1023-9. doi: 10.1016/0306-4522(87)90260-0.
Bidirectional axonal transport of glycoconjugates was studied in the sensory axons of rat sciatic nerve following injection of radiolabelled precursors into L4 and L5 dorsal root ganglia. After varying time intervals, gangliosides and neutral glycosphingolipids were isolated from anterograde and retrograde accumulation segments and radioactivity determined. Radiolabelled glycoproteins were measured in delipidated residues. These glycoconjugates were shown to undergo both anterograde and retrograde transport, accumulation occurring in roughly parallel manner for the three classes. The velocity of anterograde transport was collectively estimated at approximately 360 mm/day. Neutral glycosphingolipids, previously unknown to be axonally transported, were present in sensory axons and transported in roughly equivalent amounts as gangliosides--as judged by levels of transported radioactivity. TLC-radioautography revealed a number of molecular species in the general region of tetra- and larger glycosylceramides. Fractionation of gangliosides according to sialic acid content demonstrated the presence of mono-, di- and polysialo species at the anterograde site.
在将放射性标记的前体注射到L4和L5背根神经节后，研究了大鼠坐骨神经感觉轴突中糖缀合物的双向轴突运输。在不同的时间间隔后，从顺行和逆行积累段分离神经节苷脂和中性糖鞘脂，并测定放射性。在脱脂残渣中测量放射性标记的糖蛋白。这些糖缀合物显示出既进行顺行运输又进行逆行运输，三类物质的积累大致以平行方式发生。顺行运输的速度总体估计约为360毫米/天。中性糖鞘脂以前未知可通过轴突运输，它存在于感觉轴突中，并且通过运输放射性水平判断，其运输量与神经节苷脂大致相当。薄层层析放射自显影显示在四糖基神经酰胺及更大糖基神经酰胺的一般区域存在多种分子种类。根据唾液酸含量对神经节苷脂进行分级分离，结果表明在顺行部位存在单唾液酸、双唾液酸和多唾液酸种类。
