Effects Of Environmental Enrichment During The Period Of Abstinence On Methamphetamine Dependence

Objectives: Methamphetamine(METH)is a potent psychostimulant.It produces a strong METH craving after withdrawal.Environmental Enrichment(EE)has been demonstrated to be an effective method to treat with central disease and mental illness,including drug dependence.This project is aimed to investigate the current situation of compulsory detoxification centers in Zhejiang province and put forward some countermeasures.Subsequently,the project explored the potential effect of EE on METH self-administration and cue-induced reinstatement,using animal models.Finally,a EE model was proposed and evaluated in one compulsory detoxification center.Methods: In experiment one,200 METH dependent patients were randomly selected from five compulsory detoxification centers,based on two-stage sampling method.Questionnaires including The Obsessive Compulsive Drug use scale(OCDUS),Desires for Drug Questionnaire(DDQ),Self-rating depression Scale(SDS),Social function rating scale(SFRS)and self-made questionnaire were used in this experiment.In experiment two,32 SD rats were randomly divided into four groups: METH/EE(METH Self-Administrated in EE,n=8),METH/SE(METH Self-Administrated in SE,n=8),Sal/EE(Sal Self-Administrated in EE,n=8)and Sal/SE(Sal Self-Administrated in SE,n=8).Environmental Enrichment and Standard environment groups were compared,including METH-seeking behavior,Locomotor activity and withdrawal symptoms(depression determined by forced swimming test and anxiety by the elevated plus maze).In experiment three,an EE model with a transitional community was established in one compulsory detoxification center.The effects of EE and regular compulsory detoxification were compared,using questionnaires such as The Obsessive Compulsive Drug use scale(OCDUS)and Desires for Drug Questionnaire(DDQ).Results: The First Part:1.The survey results: 200 methamphetamine addicts showed that the mean age was 33.35±7.13 years,the mean length of education was 8.1±2.5 years,and there were 63.5% of all Unmarried or divorced.The reasons accounting for methamphetamine dependence were psychosocial factors(67.30%),physical factor(10.44%)and social factors(22.26%).Negative events of early life were dropping out of school(21.28%),living away from parents(13.42%),lacking love of parenthood(7.42%),et al.2.The levels of The OCDUS at 1,3,6,9 month(25.35±6.26 vs 35.17±8.15 vs 33.21±9.03 vs36.32±8.93,F=64.17,P<0.001),showed that the levers of 3,6,9 months were significantly higher than that of 1 month.The levels of DDQ at 1,3,6,9 months(32.13±7.47 vs 43.72±8.02 vs 37.31±9.34 vs43.04±8.44,F=59.25,P<0.001)showed the levers of 3,6,9months were significantly higher than that of 1month.3.The results of SDS showed that there was no significantly difference in four groups.The results of Social function rating scale at 1,3,6,9 months(73.72±10.01 vs 88.32±14.42 vs 74.62±12.14 vs69.98±11.64,F=83.15,P<0.001)showed that the score significantly increased at 3 month,but,significantly decreased at 6,9 months compared with 1 month.The Second Part: 1.The Locomotor activity and relapse behavior of methamphetamineself-administration model SD rat were significantly less in EE than those in SE(P<0.05).2.Mental disorders: 2.1 Levels of anxiety,The detected result showed that the number of times that rats getting into releasing arm was statistically significant among four groups(METH/EE,METH/SE,Sal/EE,Sal/SE,5.38±1.19 vs 4.13±0.83 vs 7.63±2.07 vs 6.38±1.06,F=9.42,P<0.05).Compared with METH/SE group,the times that rats getting into releasing arm significantly increased in METH/EE group(P<0.05).2.2 Levels of depression,the immobility time in the forced swimming test in four groups(METH/EE,METH/SE,Sal/EE,Sal/SE)was significantly different with each other(46.25±6.65 vs 77.63±13.10 vs 31.63±4.87 vs32.75±5.09,F=56.07,P<0.01).The immobility time in METH/EE group also significantly decreased than that in METH/SE group(P<0.05).The Third Part: After intervention with environmental enrichment abstinence model for one month,The levels of The OCDUS between two models(EE 21.28±4.69 vs SE 28.63±5.75,t=5.28,P<0.001)were significantly different from each other.The level in EE was significant lower than that in SE.The levels of DDQ between two models(EE 26.67±3.96 vs SE 39.45±6.36,t=10.45,P<0.001)were significantly different from each other,The level in EE was significantly lower than that in SE.Conclusions: 1.The majority of METH dependent patients were young adults,single and divorced.The main reasons for the initiation of METH use were psychosocial factors.The critical negative events of early life were dropping out of school,living away from parents,lacking love of parenthood.2.The effect of compulsory detoxification was not sufficient to reduce METH craving,and was difficult to improve mental disorder and social function.3.Environmental enrichment could reduce locomotor activity and cue-induced reinstatement in rats self-administering METH.4.Environmental Enrichment could alleviate the anxiety and depression in rats self-administering METH.5.Environmental enrichment model provided an alternative model of scientific detoxification,potentially reducing the rates of relapse in METH dependent patients.