Axonal degeneration distal to the site of accumulation of vesicular profiles in the myelinated fiber axon in experimental isoniazid neuropathy.
Morphometric sequential studies of pathologic changes were carried out on myelinated fibers in the lumbar ventral root of Sprague-Dawley rats administered with isoniazid, 1,500 mg/kg body weight, in a single dose. Accumulation of axoplasmic organelles with secondary paranodal retraction of myelin sheath occurred in the middle part of the ventral root as early as day 2 after the administration. On day 3, axonal degeneration started to occur, distal to the middle part, where the accumulation of axoplasmic organelles is prominent. Such accumulation with the possible blockade of the fast axoplasmic transport in the proximal axon may be directly responsible for the distal axonal degeneration. Alternatively such accumulation may be secondary to the distal axonal degeneration. The morphological sequential findings described clearly reflects the pathological events in isoniazid neuropathy.
D000818:Animals; D001369:Axons / Q000648:ultrastructure*; D006652:Histological Techniques; D007538:Isoniazid; D008297:Male; D008854:Microscopy, Electron; D009410:Nerve Degeneration; D009413:Nerve Fibers, Myelinated / Q000648:ultrastructure*; D009422:Nervous System Diseases / Q000139:chemically induced / Q000473:pathology*; D051381:Rats; D011919:Rats, Inbred Strains
D007538:Isoniazid