[Effect of curcumin on the learning, memory and hippocampal Ca+/CaMK II level in senescence-accelerated mice].

Objective To explore effect of curcumin in different concentrations on learning and memory of senescence-accelerated mice(SAM) and their possible mechanisms.Methods Mice were randomly divided into six groups:the SAMR1 normal control group,the SAMP8 model control group,the SAMP8+solvent(the peanut oil) control group,SAMP8+ low,middle and high dose curcumin groups.Mice were gastrogavaged for 25 successive days.On the next day of ending the experiment,changes of learning and memory in mice of each group were observed by Morris water maze.The hippocampal [Ca2+]i was determined.Expressions of hippocampal calmodulin-dependent protein kinase Ⅱ(CaMKⅡ) and Calmodulin(CaM) mRNA were detected using Western blot and reverse transcription polymerase chain reaction(RT-PCR) respectively.Results The latency to find the hidden platform was remarkably prolonged,the hippocampal [Ca2+]i was markedly increased,the expression of CaMKⅡ in the hippocampal membrane and the level of hippocampal CaM mRNA were significantly reduced in the SAMP8-model control group(P0.05,P0.01).The latency to find the hidden platform was remarkably shortened in the SAMP8+ middle dose curcumin and the SAMP8+high dose curcumin groups(P0.01).The hippocampal [Ca2+]i was markedly lowered,the expression of CaMKⅡ in the hippocampal membrane and the level of hippocampal CaM mRNA obviously increased in the SAMP8+ low,middle and high dose curcumin groups(P0.05,P0.01).Conclusion Curcumin could improve learning and memory Ca2+/capacities of SAM by lowering hippocampal [Ca2+]i overload,increase the hippocampal CaM mRNA level and CaMKⅡ expression in the hippocampal dose-dependently.