Detection of apoptosis in the brain of the zitter rat with genetic spongiform encephalopathy.

Zitter rat develops genetic spongiform encephalopathy accompanied with whole-body tremors and flaccid paresis. To elucidate the mechanism of a neuronal cell death in the brain, we determined involvement of apoptosis in this rat. By Northern blot analysis, the elevation of mRNA levels were observed in c-jun, c-fos, c-myc and p53 genes which were induced by apoptotic signals: conversely, expression of bcl-2 was shown to be decreased in the zitter rat brain in contrast to the WTC control rat. Furthermore, TUNEL staining of fragmented DNA indicated apoptotic morphology in this brain. These results strongly suggested that the spongiform encephalopathy of the zitter rat was due to apoptosis in the brain cells.