CaMKII activity in the hippocampus is important for expression of drug-induced CPP. Repeated injections of amphetamine during CPP conditioning increase CaMKII activity in the rat hippocampus.257,258 Expression of amphetamine CPP is attenuated by pretreatment with intrahippocampal injections of KN93 during conditioning257,258 or immediately before the CPP test.257 However, intra-NAc injections of KN93 during the conditioning phase have no effect.258 Expression of morphine CPP in rats is also attenuated by intrahippocampal injections of KN62 or KN93 during conditioning255,256 and immediately before the CPP test.256
