LTD Blocking Peptide Effect For HU210 On Recognition Memory In Mice

Marijuana (cannabis sativa) has been used as a drug for5000years. The early applications of cannabinoid were ache agent and anesthetization, but lots of side effects were discovered following the increasingly wide application. Cannabinoid, he main ingredient of marijuana which have hallucinogenic effect, cause loss of consciousness, decreased attention and impaired memory. At the same time, the incidence of mental disorders increased. Inparticular, cannabinoid application causes addiction and severe impairment of memory, including recognition memory, the underlying mechanism of which remains elusive.In this experiment, HU210was applied on the three phases of Novel Object Recognition Task(NOR) to test the influence of HU210in the three stages of recognition memory in C57BL/6J mice.NOR was designed by Ennaceur and Delacour based on the rodents innate character of exploring novel object and new environment, which is a kind of non-spatial working memory model. NOR consists of three parts:habituation phase, familiariztion phase, test phase. In the NOR task, rodents have to adapt to the around envirment. After that they also should be familiar with the object in the apparatus, and the time in exploring a novel object and familiar object in the test phase are recorded respectively to assess their ability of recognition memory.In this study, the experiment was divided into two parts. The first part was to established NOR model with C57BL/6J, then synthetic cannabinoid, HU210was applied in the three phases of NOR to evaluate HU210influence on long-term memory in mice. The results showed that:(1)In the acquisition stage, after treatment, there is significant difference between novel recognition index and familiar recognition index(p <0.01), namely distinguished the novel object and familiar object and showed the preference of novel object.(2)In the consolidation stage, there was no difference between novel object recognition index and familiar object recognition index(p>0.05), namely mice could not distinguish novel object and familiar object. HU210induced amnesia.(3)In the retrieval stage, after HU210injection, there is no difference between novel object recognition and familiar object recognition(p<0.01), namely mice could distinguish the novel object and familiar object. In the second part, a kind of synthetic LTD blocking pebtide was used before HU210to examine the role of LTD in HU210’s impact on the acquisition stage, consolidition stage and retrieval stage. Our results showed that LTD blocking pebtide could block HU210’s effect on recognition memory consolidation in mice.