Abstract: Objective To study the effect of acute lead exposure on Ca²⁺-CamkⅡ signal in rat hippo campus.Methods Hippocam palslices of 30 day sold heathy rat were collected and incubated with lead acetate(20 μmol/L)and non lead ace tate in artificial cerebro spinal fluid(ACSF)for the control,glutam ate,CaM KⅡ inhibitor(KN-93),and glutamic acid + lead ace tate group.Brain slices were collected after 30 min of culture.Western Blot was adopted to detect the activity of cyclic adeno sine-3'-5' mono phosphate response element binding prote in(CREB).Results CREB activity in the lead groupdecrea sed significantly with the time of lead exposure.CREB activity increa sed by 47% in glutam ate group and decreased by 20%,45% in KN-93 and glutamic acid+ lead acetate groups.There was no significant change in total CREB expression.Conclusion A cute lead poisoning may inhibit the activity of Ca MKⅡ and affect the downstream signaling molecules resulting in learning and memory damage.