Effect Of Lycium Barbarum Polysaccharide On Cognitive Function Of Mental Fatigue Induced Psychological Sub-health Model Rats

Objective: To establish a mental fatigue type psychological sub-health model in rats,and to observe the preventive effect of Lycium barbarum polysaccharide on cognitive function of mental fatigue type sub-health rats and provide theoretical guidance for prevention and intervention of psychological sub-health.Methods: 50 rats of clean grade Sprague Dawley,according to the level of body weight were randomly divided into 5 groups: normal control group(C,n=10),model control group(PS,n=10),the model for the normal saline group(PS+NS,n=10),the model for low-dose LBP group(PS+LBP20mg/kg,n=10),the model LBP high-dose group(PS+LBP40mg/kg,n=10).The modeling process is mainly divided into three parts,namely,the environmental adaptation period is 7 days,and the uncertain stress of drinking water training for the first 7 days and the formal modeling stage for 21 days.Model consists of four factors,respectively with chronic sleep deprivation,activity limitation,irregular diet and empty bottles of uncertainty to simulate the stress of modern society brainworkers' long-term lack of sleep,sedentary life style,fewer activities,irregular diet and the uncertainty work stress and pressure.The normal control group fed naturally during the experiment,no experimental and drug intervention.The PS group,PS+NS group,PS+LBP20mg/kg group and PS+LBP40mg/kg group rats were given experimental and drug intervention according to the model program.After examining the modeling by identifying whether rats in disease state(body weight,body temperature,in general),inspecting activity and emotion(open field test,the elevated plus maze test),and learning and memory tests(eight arm maze)to examine several Aspects of brain fatigue type mental sub-health rat model's major core symptoms(i.e.non disease status,anxiety or depression emotional experience and learning and memory function),to examine and evaluate the intervention of new model and drugs.Results: 1.Identification of mental fatigue type sub-health rat model The 21 th day's body weight between Control group and PS group was significantly difference(P < 0.05).The body temperature of rats in group Control and group PS were normal,and the fever caused by disease was excluded.The 7th day,the 14 th day and the 21 th day's body weight between the Control group and the PS group was significantly difference(P < 0.05).The rats in group PS were lower than those in Control group,and the body weight was significantly slower than that in Control group(P < 0.05).The difference between Control group and PS group in total distance and average speed were significantly(P < 0.05),open field level movements in rats of the two groups had significant difference(P < 0.01).The ratio of open arm retention time between the Control group and the PS group was significantly difference(P < 0.05).In the Day6,the results of the test of the eight arm maze time difference between Control group and PS group of rats was statistically significant(P < 0.05).In the Day7 the working memory error number between Control group and PS group was statistically significant(P < 0.05).2.Effects of LBP on the rats in five groups(1)The weight of the Control group was significantly different between thePS+LBP40mg/kg group,PS+LBP20mg/kg group,PS+NS group and PS group(P < 0.01).The weight of PS+LBP40mg/kg group and PS+LBP20mg/kg group were significantly higher than those in group PS+NS and group PS(P < 0.01).The body weight growth of rats between the groups in first weeks,second weeks and third weeks were statistically significant(P < 0.01).(2)The total distance,average speed,vertical stand number,horizontal cross cell number in the open field between Control group and PS group were statistically significant(P < 0.05).The vertical stand number in open field level was statistically significant between PS+LBP20mg/kg group and PS group,the number of squares crossed in open field between PS+LBP20mg/kg group and PS group was statistically significant(P < 0.05).The number of vertical stand level and the number of squares crossed between PS+LBP40mg/kg group and PS group was statistically significant(P < 0.05)(3)The open arm entry frequency and the open arm retention time were statistically significant between Control group and PS+NS group(P < 0.05).The number of open arm entry was significant difference between the PS group and the Control group and the PS+LBP40mg/kg group(P < 0.05).PS group,Control group,PS+LBP40mg/kg group and PS+LBP20mg/kg group had significant differences in the duration of open arm retention time(P < 0.05).(4)The eight arm maze test's total test time was significantly difference between PS+LBP40mg/kg and PS+NS in for(P < 0.05).The eight arm maze test's reference memory error frequency in sixth days between Control,PS+NS group,PS group was significantly difference(P < 0.05).The eight arm maze test's reference memory error frequency between PS+LBP20mg/kg group and PS+NS was significantly difference(P < 0.05).The eight arm maze test's reference memory error frequency in seventh days between PS+NS group,PS group was significantly difference(P < 0.05).The eight arm maze test's right frequency in sixth days between Control,PS+NS group,PS group was significantly difference(P < 0.05).Conclusion: 1.By using chronic partial sleep deprivation,irregular diet,failure of bottle uncertainty psychological stress and social fatigue 21 days to construct a rat model of mental fatigue type.Observing the general situation of body temperature,body weight,open field test,the elevated plus maze test and the eight arm maze test to indicate that the construction of mental fatigue type sub-health psychological model are basically success.2.The symptoms of mental fatigue type psychological sub-health rat model is the increasing autonomic activities,a slow increase of body weight and mental tension or irritability caused the increase of anxiety and the decline of learning and memory.3 In the process of model construction of mental fatigue type psychological sub-health,LBP can partially prevent and improvement the rats' general condition,autonomic activity,anxiety,learning and memory decline.