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Introduction: In this study the effect of extracellular trans zinc and voltage sensitive calcium channels on different aspects of learning and memory has been investigated. Materials and Methods: This is an experimental study in which the effect of a calcium channel antagonist (Verapamil) and zinc chelator (Ca-EDTA), on passive avoidance learning (shuttle box apparatus) has been examined by intraperitoneal administration of defferent doses of these drugs. Data was analyzed using one way analysis of variance. Results: Result of intraperitoneal injection of 100 milimolar Ca-EDTA indicated that it has no effect on the acquisition, consolidation, and retrieval of passive avoidance learning. Verapamil (100 and 150 micrograms) as a L-type voltage gated calcium channel antagonist, decreased acquisition and consolidation but not retrieval of passive avoidance behaviour. These effects were dose dependent. The simltaneous effect of Ca-EDTA and verapamil was also studied. Ca-EDTA (100milimolar) and verapamil (100 micrograms) have negative effects on consolidation of passive avoidance learning. Conclusion: Probably, common mechanisms are involved in acquisition and consolidation of passive avoidance learning, and zinc and calium ions play interactive roles in this aspect.