Effect Of Banxia-Houpo Decoction, Magnolol And Honokiol On Gastrointestinal Movement, And Their Anxiolytic And Antidepressant Effects

AIM1. To study the effects of differernt doses of magnolol, honokiol and Chinese herb Magnolia bark on the isolated smoth muscle of gastrointestinal tract.2. To study the effects of different doses of Banxia - Houpo decoction, Magnolia bark, magnolol and honokiol on the gastric emptying and intestinal propulsive activity in mice.3. To assess the anxiolytic and antidepressant effects of different doses of Banxia-Houpo decoction, magnolol and honokiol on mice.METHODS1. Routine experimental methods for isolated gastric fundus strips of rat and isolated ileum of Guinea pig were adopted to measure the gastric tension. To assess the effects of magnolol 10-3M10-4M,10-5 M, and honokiol 10-4M,10-5 M,10-6M on the contractive gastric fundus strips caused by Ach and 5-HT, and contractive ileum of Guinea pig caused by Ach and CaCl2, and assess the contractive effect of Magnolia bark on isolated gastric fundus strips of rat.2. Treated with one time, three times, and 10 times routinal doses of Magnolia bark of adult human, or one time, three times routinal doses of Banxia-Houpo decoction daily for seven days on mice, the method of nuclein and pigment methylene blue were used to measure the gastric residual rate of muclein and intestinal propulsive ratio of nutritional semi-solid meal. Using the same method to assess the effects of magnolol (0. 5mg/kg,2mg/kg,20mg/kg ) andhonokiol (0.5mg/kg ,2mg/kgA20mg/kg )on gastric emptying and intestinal propulsive function.3. After oral administration daily for seven days with the three different doses of Banxia - Houpo decoction ( 1,3, and 10 times of routinal doses of adult human), magnolo(0. 5mg/kg,2. Omg/kg,20mg/kg) and honokiol (0. 5 mg/kg, 2. Omg/kg,20mg/kg) in mices, the elevated plus-maze test (EPM) was used to assess the anxiolytic effect of the three kinds of durgs, the methods of tail sus-pention test and forced swimming test were used to assess their antidepressant effects.RESULTS1. Magnolol and honokiol significantly inhibited the contractility of isolated gastric fundus strips treated with Ach or 5-HT and the contractility of isolated il-eum treated with Ach or CaCl2, and all behaved as non-competitive muscarinic antagonists; Magnolol and honokiol inhibited the contraction induced by Ach in Ca + -free medium and extracellar Ca + -dependent contraction induced by Ach. Magnolia bark can cause constraction of isolated gastric fundus strips of rat dose-responsively.2. Each guoup of Banxia-Houpo decoction, Magnolia bark, magnolol and honokiol could significantly decreased the residual rate of muclein in stomach and increased the intestinal propulsive ratio in mice. Compared with prepulsid, there is no significant difference.3. After treated for seven days, 0.5mg/kg honokiol could significantly increased the open arms enter ( OE) and 2mg/kg honokiol prolonged the open arms time(OT) in the EPM. Banxia-Houpo decoction ( one time routinal dose), magnolol (2mg/kg) and honokiol (0. 5mg/kg, 2mg/kg, 20mg/kg) significantly decreased the accumulative immobility time in tail suspention test and forced swimming test. In the open field test, there is no difference between each group in times of step over the square and times of standing of mice.CONCLUTION1. The inhibited effect of magnolol and honokiol on contractility of the smoth muscle of isolated gastric fundus strips of rat and isolated ileum of Guinea pig was associated with a calcium-antagonistic effect.2. Banxia-Houpo decoction, Magnolia bark, magnolol and honokiol improved the gastric empting of semi - solid meal and intestinal propulsive activity in mice.3. Honokiol had a obvious anxiolytic effect and Banxia-Houpo decoction, magnolol, and honokiol had a antidepressant effect.