The Effect Of The Late Embryo Exposal To LPS On The Protein Level Of Syt I In Dorsal Hippocampus Of Middle-aged CD-1 Mice

BackgroundThe gradual decline of learning and memory with age is a common phenomenon in human beings and the rodent. However, the underlying neuromechanism of the age-related impairment of learning and memory is not yet clear. The current view is that the decline of spatial learning and memory may be caused by the changes in the level of synaptic protein in the hippocampus and neocortex. Syt I is considered to be related to the impaired learning and memory with aging. Our previous study showed that Syt I increased specifically in the dorsal hippocampus of aged SAMP8 mice, which was related to the impairment of age-related spatial learning and memory. Therefore, Syt I is considered to be the candidate synaptic protein related to learning and memory abilities. Another study also showed that the late embryo exposal to LPS during the advanced stage of fetation could imitate inborn intrauterine infection, and study the following influences on the lateral development. Recently, our study indicated that the late embryo exposal to LPS had impact on the spatial learning and memory in the middle-aged CD-1 mice. However, the underling mechanism is still unclear. It was presumed that the anormaly expression of Syt I protein might be invloved in the mechanism. To test this hypothesis, the immunohistochemistry method was applied to investigate the level of Syt I in dorsal hippocampus of late embryo exposal to LPS in middle-aged CD-1 mice.Objective To explore the effects of late embryo exposed to LPS on the content of Syt I in dorsal hippocampus in middle-aged CD-1 mice. Methods Two groups (late embryo exposed to LPS group and homeochronous control group, both n=15) of middle-aged CD-1 mice were used after they were assessed behavioral performace and the expression of Syt I was detected by the immunohistochemistry method (S-P method).Results The expression of Syt I was detected in the DG, CA3 and CA1 of dorsal hippocampus of the mice. The relative amount of Syt I in the DG in the late embryo exposed to LPS group was significantly higher than that in the control group (P < 0.05).Conclusion Syt I expressed in the DG, CA3 and CA1 of dorsal hippocampus in CD-1 mice. The relative amount of Syt I was influenced by LPS only in the DG of dorsal hippocampus. The relative amount of Syt I in the DG in the late embryo exposed to LPS group was significantly higher than that in the control group(P < 0.05).