CHANGES IN THE ADP-RIBOSYLATION STATUS OF SOME HIPPOCAMPAL PROTEINS ARE LINKED TO KINDLING PROGRESSION

THE N-methyl-D-aspartate (NMDA) receptors are a class of excitatory am ino acid receptors in the brain which are important for the induction of kindling and kindling-like phenomena. Post hoc sodium nitroprusside -induced ADP ribosylation of some proteins (particularly a p43 and a p 39 protein) in homogenates from stimulated hippocampus was reduced at preconvulsive stage II and stage V (tonic-clonic seizures) of dentate gyrus kindling compared with controls. This effect, which probably ref lects enhanced endogenous ADP ribosylation, depends on the progressive activation of the NMDA receptors and on the generation of nitric oxid e (NO). The early occurrence and the persistence of these modification s suggest they may be associated to the long-lasting changes in neuron al function induced by kindling.