FIG. 4.

Abnormal SYN immunostaining in BDV-infected rat brain. Note the clustering of SYN IR within the inner molecular layer of the DG at 25 days p.i. (compare panels A and B). SYN staining is also found in the cell bodies of dentate granule cells (arrowed cells in panel D, shown at a larger magnification in the boxed area). By day 45 p.i., the corpus callosum, which is usually negative for SYN staining in control rats (panel E), exhibits a patched IR in infected animals (arrows in panel F and boxed area). The immunostaining accumulates in axonal blobs, indicating an abnormal axoplasmic flow and a poor transport of SYN to the synaptic terminals. Magnification, ×150.