• hemidiaphragm;
  • IgG anti–GalNAc-GD1a antibodies;
  • neuromuscular junctions;
  • nerve terminal;
  • ventral root


Introduction: We investigated the localization of a ganglioside, N-acetylgalactosaminyl GD1a (GalNAc-GD1a), in peripheral nerves with an IgG anti–GalNAc-GD1a antibody, which was produced in rabbits immunized with GalNAc-GD1a. Methods: Teased fibers from ventral and dorsal roots and hemidiaphragm sections of rats were assessed using fluorescent double- and triple-labeling methods. Results: The nodal and paranodal regions of teased fibers from ventral roots were immunostained with IgG anti–GalNAc-GD1a antibodies. After collagenase treatment, no staining was seen with IgG anti–GalNAc-GD1a or anti-NF200 antibodies, whereas α-bungarotoxin selectively stained nerve terminals. In cross-sectional and longitudinal sections of rat hemidiaphragm, IgG anti–GalNAc-GD1a antibodies overlapped with α-BuTx and anti-NF200 antibodies, indicating that GalNAc-GD1a is localized to the nerve terminal. IgG anti–GalNAc-GD1a antibody staining also overlapped with that of AChR clusters and syntaxin-positive presynaptic nerve terminals. Conclusion: GalNAc-GD1 is localized in both pre- and postsynaptic nerve terminals of neuromuscular junctions. Muscle Nerve 46: 705–710, 2012