Regulation of aberrant neurofilament phosphorylation in neuronal perikarya. III. Alterations following single and continuous /gB,ß′-iminodipropionitrile administrations

摘要: β,s′-Iminodipropionitrile (IDPN) administration produces giant neurofilament-filled axonal swellings in the first proximal internodes of large myelinated sensory and motor fibers without any accompanying degeneration. In present study, we asked whether are sufficient to elicit aberrant neurofilament (NF) phosphorylation neuronal perikarya. Rats were given a single intraperitoneal (i.p.) injection IDPN (2 g/kg) followed by (0.1%) drinking water (continuous exposure) or tap (single for two days 7 weeks. Immunoreactivity phosphorylated NF (pNF) epitopes (using monoclonal antibodies 6–17 7–05) was observed L4 L5 dorsal root ganglia (DRG) neurons beginning between one 5 days, corresponding development swellings. Quantitation DRG demonstrated maximal numbers immunoreactive cell bodies pNF (46–51%) week. The number immunostained cells maintained animals continuous exposure, but declined significantly (P < 0.001) rats 26 ± 0.80% 6 0.04% at 3 weeks, respectively. Ventral fibers, which undergo atrophy distal swellings, showed intense immunoreactivity marked reduction complete lack immunostaining antibody 2–135 (directed against non-phosphorylated epitopes); pretreatment with alkaline phosphatase reversed this staining pattern. separate similar phosphatase-sensitive also atrophic 4 weeks following nerve crush. It is suggested that from IDPN-treated arises secondarily an alteration retrogradely transported ‘trophic’ signal(s) neuron due presence Furthermore, pNFs axons may correspond stationary slowly moving NFs axoplasm.