Modulation of endogenous ADP-ribosylation in the kindling model of epilepsy.

Abstract

ADP-ribosylation occurs through the transfer of an ADP-ribose moiety from NAD to specific substrate proteins. This biochemical process catalyzed by ADP-ribosyltransferase is concerned in the regulatory mechanisms of numerous cellular functions.'* ADPribosylation reactions are classified into two major groups: mono ADP-ribosylation and poly ADP-ribosylation. Exogenous toxins, especially pertussis toxin and cholera toxin, induce the ADP-ribosylation. l7 '' Occurrence of the endogenous ADP-ribosylation in the brain has been revealed in recent studies and it is suggested that the endogenous ADP-ribosylation regulates some neural f~nc t ions .~ l9 The kindling is a quite suitable model in the search for the basic mechanisms of epilepsies. We have already reported the alteration in the ability of Gs to bind GTP and alteration of pertussis toxin-catalyzed ADP-ribosylation in the amygdaloid kindled brain.5-7 G proteins