Study Of Liquiritin To Treat Depression On Pharmacodynamics And Its Possible Antidepressant Mechanisms

Depression is an affective disorder disease with higher outbreak rate . Tthe symptom is diverse, such as the motion low fall, appetite and sleep obstacle, cynical and suicide obsession, and so on. At present ,the synthetic chemical medicines were mainly taken as treatment to depression have been proofed that have the defects and side effects and expensive .Medicinal plants from natural resources,especially the traditional Chinese medicine have a long time experience in cure depression.Among many traditional Chinese medicine recipes ,the classic recipe"Ganmai Dazao Decotion"showed significant antidepressant effect.And the effect element is Liquiritin.We want to make use of the modern pharmacology to learn method evaluate Liquiritin the treatment suppresses the efficacy of medicine and possible mechanis ms of depression.Study of Liquiritin to treat depression on pharmacodynamics1 Effects of Liquiritin on Behavior despair of animal1.1 Forced swimming test(FST)The test was performed essentially as described by Porsolt et al. (1977). Mice were individually placed in a vertical glass container (20 cm high, 10 cm in diameter), containing 16cm of water maintained at 22°C–25°C. The total duration of immobility was recorded during the last 4 min of the 6min test period. The immobility time was recorded using the EthoVision video tracking system.1.2 Tail suspension test(TST)The grouping and drug administration matter were the same as FST .The mouse was individually suspended by its tail with a clamp (2 cm from the end )for 6min and the duration of immobility was recorded in last 5min.2 Effect of liquiritin on induced to the medicine of the depression animal modelAfter administration of liquiritin for 2 days, and then give reserpine to induce depression symptoms, observe the ptosis, akinesia and hypothermia which occurred by reserpine.3 Unpredictable Chronic stress test(CUMS )After chronic unpredictable stress which exerted on each rat excluding the control ones for 3 weeks , we found that the liquiritin can improve the symptoms which appeared in the mod- el rats. The three doses of liquiritin 40mg/kg,20mg/kg,10mg/kg) all increased the quantity of the water wi th carbohydrate which was drunk by rats. The rat weight increment. The number of crossings- and rearings in the open field test (OF) and stop over time of central space and number of excrement were increased as well. according to our findings of water maze , Shorten the Escape l atent period of the third day and the forth day obviously, and raise to cross the Platform num- ber of times.Study on mechanism of liquiritin on depression models in rats1 Effects of liquiritin on monamine transmitter of inside brain in the CUMS ratsMake use of the CUMS model.And adopt HPLC-ECD measurement brain inside transmitter and it metabolizes the outcome in the rat brain by CUMS. According to our findings,show that model group showed reduced the 5-HT,NE,DA level (**P<0.01,*P<0.05),and increased the 5-HIAA,5-HIAA/5-HT,DOPAC level . After treatment of Clomipramine and middle dose of liquiritin , the level of 5-HT,NE increased ( **P<0.01, *P<0.05 ) ,but reduced the 5-HIAA,5 - HIAA/5-HT ( **P<0.01, *P<0.05).and there have no significant changes to DA and DOPAC.2 Effects of liquiritin on COR,ACTH,IL-2,IL-6 of the bloodMake use of the CUMS model. Make use of the immunity analysis method measurement the content of the IL-2, IL-6 in plasma andACTH, COR in serums.According to our findings, Model group showed increased IL-1? and cortisol level versus normal group(P<0.05). after treatment of Clomipramine and middle dose of liquiritin ,the level of IL-1? , IL-6 and cortisol reduced to normal (P<0.05),but high and low dose have no significant changes.And in this experiment ,there has no significant change of IL-2 before and after stress .