Study On The Antitussive, Antiasthmatic And Expectorant Effect And The Mechanism Of The Ethanol Extract From Flower Of Eriobotrya Japonica

Objective: To study the effects and mechanism of the ethanol extract from Flower of Eriobotrya japonica (FEJ) on the antitussive, expectorant and antiasthmatic effect for clinical application.Methods:1. Antitussive, expectorant and antiasthmatic effect of FEJ.①Using cough model induced ammonia water, the incubation period of cough time and 3 minutes cough in mice were recorded from begining ammonia spray.②With cough model induced Citric acid, the incubation period of cough time and 5 minutes cough in guinea-pig were recorded from begining citric spray to presenting cough.③According to phenol red standard cures, phenol red secretions in every groups were calculated.④Using asthmogenic method by nebulization induced through acetylcholine bromide and histamine phosphate, the latent period of asthmatic model in inhaling 0.1%His and 2%Ach were recorded after administration of FEJ.2. Mechanism of FEJ on the antitussive and antiasthmatic effect.①The peripherally-acting antitussive effect of FEJ was investigated by inhibiting ATP sensitive K+ ion channel and releasing substance P from C-fibre induced by capsaicin in guinea pigs.②Models of acute inflammatory reactions of xylene induced mouse ear edema was performed to study the anti-inflammatory effects.③Mice asthma model was duplicated by OVA through sensitizing and challenging, the number of EOS in BALF and NO in pulmonary tissue homogenates were determined; the contents of IL-8, IL-10 in the serum were (respectively) measured by ELISA; after H-E staining, the pathological changes of bronchus and morphological changes of the bronchus were observed with Light Microscope; the expression of NF-κBp65 in the lung tissues were determined immunohistochemistry.Results:1.Experimental study on antitussive, expectoration and antiasthma.①FEJ decreased significantly the cough of mice and guinea pigs (P<0.01); the latency of cough times were significantly prolonged (P<0.01).②The effect of the excretion of phenol red in bronchus of mice showed that, there was very significant difference between FEJ groups with control group (P<0.01).③FEJ increased significantly the latency of 2%Ach+0.1%His-induced asthma of guinea pigs (P<0.05), It has distinguished antiasthmatic effect.2. There is significantly difference in releasion of substance P from c-fibre. FEJ maybe not work through influencing ATP-sensitive K+ ion channel to relieve cough.3. FEJ inhibited significantly mouse ear edema induced by xylene; It was found that in FEJ treatment groups bronchi and reaction of lung tissue was improved in varying degrees; exudate of lumen, the increasing of basement membrane and the defective mucous membrane on the wall of the bronchus were reduced; at same time the inflammatory cell were reduced. FEJ has significant anti-inflammatory effect. FEJ could decrease the levels of IL-8 in the serum of mice (P<0.05), while the levels of IL-10 were significantly increased (P<0.05). NO concentrations in pulmonary tissue homogenates were decreased; the number of EOS was decreased obviously in BALF of asthma mice (P<0.05); the result of immunohistochemistry implied that FEJ decreased obviously the expression of NF-κBp65 in lung tissue (P<0.01).Conclusion: FEJ has antitussive, antiasthmatic, expectorant actions on animal experiments. Its mechanism were maybe associated with decreasing the release of IL-8 in the serum of mouse, increasing the release of IL-10, suppressing the expression of NF-κBp65 and inhibiting NO signaling moleculars and reducing the release of inflammatory mediators. The experiment results provide experiment basements for the clinics of FEJ.