Neurofibrillary tangles in experimental neurolathyrism in rats induced by imino-dipropionitrile (IDPN). 1. Fine structural changes in the spinal cord and dorsal root ganglia.

Anterior horns of the spinal cord from cervical and lumbar regions and dorsal root ganglia from these same levels were studied for ultrastructural changes in imino-dipropionitrile (IDPN) treated rats. Normal saline-injected rats, treated identically, served as controls for this study. In the spinal cord axonal balloons or dystrophic axons appeared in lightly myelinated or unmyelinated axons within 24 h after the third injection of IDPN. At this time hind leg paralysis had not yet developed. In addition to axonal changes, a few dendrites also showed neurofibrillary degeneration. Central chromatolytic changes were observed in most of the neurons, with evidence of generalized edema present within the cord. In the dorsal root ganglia axonal balloons were very prominent and showed neurofibrillary hypertrophy. Neurofibrillary material was also noted in the perikarya of medium-sized ganglion cells.