Figure 5.

Chronic, slow, application of kainate (100 μM) causes optic nerve lesions that have the major features of MS. (a and b) Few oligodendrocytes are viewed with antibodies to 2′,3′-cyclic nucleotide 3′-phosphodiesterase within the resulting plaques. Asterisks in a and b denote the center of an area shown at a higher magnification in b. (c) The presence of myelin basic protein is greatly reduced in the damaged regions (star). (d) TUNEL-labeled elements (arrows) located at the edge of a lesioned area (star). (e and f) Axons remaining within the plaques (f) usually have a smaller caliber and present more swellings (arrowheads) as well as dislodgment (arrows) than normal axons (e), as illustrated by neurofilament immunohistochemistry. (g and h) Toluidine blue staining of vessels (arrowheads) in a control nerve (g) and within a damaged area (h), shows evidence of inflammation in the latter in the form of an increased number of large perivascular cells. The nerves illustrated were examined at 4–7 days after initiating the treatment with kainate. [Bar = 140 μm (a and c); 70 μm (d); 35 μm (b, g, and h); and 14 μm (e and f).]