To study the effect of dopamine (DA) On lCa2+- calmoudulin. dependent protein kinase Ⅱ (CCDPK Ⅱ) activity in hippocawpus. METHODS: Using rat hippocampal slices as an vitro model, the aetivity Of CCKPK Ⅱ was examined by the method of 32-P incorporation, RESULTSI: Exogenous DA reduced CCDPK Ⅱ activity in hippocampal slices in a concentration-and time-pendent manner Removal of extracellular caleium antagonized the DA-induced inhibition of CCDPK Ⅱ activity, partially or completely. The activity of CCDPK Ⅱ was markedly decreased by apomorphine(a nonselective DA receptor agonist)．SKF38393 (a selective D1-like DA receptor agonist), or quinpimle (a selective D2-like DA receptor agonist). The inhibition of CCDPK Ⅱ activity induced by exogenous DA was abolished by preincubation with Sch-23390, a selective D1-like DA receptor antagonist, Or domperidon, a selective D2-1ike DA receptor antagonist. CONCLUSION: DA has all inhibitory effect Oll CCDPK Ⅱ activity in rat hippocampus, related to sdmulation of D1-like and D2- like receptors and calcitmainflux.