Selective alterations of RNA in rat hippocampus after entorhinal cortex lesioning.

In vitro translation products from RNA of rat hippocampus after deafferentation by entorhinal cortex lesions were analyzed by two-dimensional gel electrophoresis. Although hippocampal total RNA yield was not affected 14 days after the lesion, analysis of the gels showed reproducible changes in the steady-state level of several transcripts. Glial fibrillary acidic protein RNA increased 2-fold over control hippocampi RNA. Moreover, seven other transcripts of unknown identity had increased prevalence in the denervated hippocampus. The changes, which ranged from 2- to 20-fold, involved mRNA encoding small slightly acidic polypeptides: 12 kDa (pI 5.6), 13 kDa (pI 6.1), 20 kDa (pI 5.8), 31 kDa (pI 5.7), 33 kDa (pI 5.7), 35 kDa (pI 5.6), and 53 kDa (pI 5.4). These results suggest new molecular markers for analyzing the complex mechanisms of synaptic reorganization in the dentate gyrus after deafferentation.