Effect Of Paradoxical Sleep Deprivation On Spatial Learning And Memory-its Mechanisms And Prevention

BackgroundSleep and Periodical awareness are surviving necessities of human-being and mammal. Sleep deprivation is a common stressor of night shift careers as well as some other special careers. It draws more and more attention while there has been faster life rhythm and heavier career pressure. According to epidemiological data, sleep deprivation can break our body's immunity, awareness, judgment and the faculty of memory down which does harm to work efficiency and security. According to the past reports, sleep deprivation may cause kinds of neurological system changes during the physiological changes, yet its mechanism is uncertain of.AimParadoxical sleep deprivation rats model had been set up to observe whether sleep deprivation can affect rat's spatial learning and memory, and we can analyze its mechanism of influence on rats'learning and memory. The precautionary function of acanthopanax was observed.MethodsParadoxical sleep deprivation (PSD) was performed by using the"Flower pot technique". Spatial learning task were performed with Morris water maze. The change in form of CA1 area of hippocampus, the micro-change of neuron and the expression of apoptosis of related protein in chondrosome at different sleep deprivation time point were observed by Nissl stain, immunohistochemical method, transmission electron microscope (TEM), and Western-Blot technique.Results1. The results of the Morris water maze shows that with the procedure of the Paradoxical sleep deprivation (PSD), the latency and the exploring distance had been shortened in both sleep deprivation group and control group. The rats were more likely behaving near the area of platform. The statistic tendencies of latency time of two groups were similar. But sleep deprivation group spend much more time than control group in latency I, and it's statistically different. All parameters above showed no statistic different in latency II of sleep deprivation.2. The Nissl stain shows that sleep deprivation decreases the number of the cells in CA1 area of hippocampus. And it also looses the range of the cells, and large quantity of vacuolus had been found. TEM shows obvious dropsy in neuraxis, endoplasmic reticulum (ER) expansion, chondrosome intumesce and the dim structure of cristae. The number of chondrosome was decreasing, and becoming vacuolus. 3. Through immunohistochemical method, it is showed that BAX in CA1 area of hippocampus shifted into chondrosome on going with sleep deprivation. The expression of BAX in intracytoplasmic decreased; the Cyt-c in chondrosome released to cytoplasm and brought up Cyt-c expression in cytoplasm. Western-Blot shows the same results of immunohistochemical method.4. After intragastric administration with acanthopanax liquid, the results of Morris water maze of different groups showed that the latency I of prevention group was less than SD group. The damage of CA1 area of hippocampus was relieved.Conclusion1. Sleep deprivation can lower the forming and maintaining abilities of rat's spatial learning memory without spatial working memory.2. Sleep deprivation can cause obverous change in form of CA1 area of hippocampus and its micro-structure and function which may be the cytology foundation of effects of sleep deprivation on learning and memory.3. Sleep deprivation causes apoptopsis of hippocampal neurons. Its mechanism may closely relate with the mitochondrial apoptopsis.4. Acanthopanax liquid does have some effect on preventing the mitochondrial apoptopsis of hippocampal neurons from sleep deprivation and antagonizes sleep deprivation by improving the state of cell.