KAINATE-EVOKED MODULATION OF GENE-EXPRESSION IN RAT-BRAIN

Kainate is a glutamate analog that produces neuronal excitation result ing in seizures within hours following its intraperitoneal injection i nto adult rats. Then, at 2-3 days after the treatment, neurodegenerati on of apoptotic character can be observed in limbic system. As a conse quence, plastic reorganization and glial reactivation phenomena occur. These physiological and pathological responses are reflected by speci fic changes in gene expression, that can be dissected according to the ir spatio-temporal patterns. The early phase of gene expression observ ed in all hippocampal subfields appears to reflect a sudden burst of s piking activity. Changes in mRNA levels restricted to dentate gyrus ar e suggestive of a link to neuronal plasticity. The late gene expressio n response implies its correlation either to neuronal cell death or gl ial reactivation, depending on cellular localization of gene products. Thus analysis of the temporal and spatial gene expression pattern in the hippocampus after kainate treatment may provide clues revealing sp ecific phenomena to which gene expression could be attributed.