Areca On Gastrointestinal Pacemaker Cell In The Spleen And Stomach Qi-stagnation Mice

Objective：1. To establish mouse model of spleen and stomach Qi-stagnation, and provide agood platform for the study of traditional Chinese medicine mechanism for promotinggastrointestinal motility.2. To study the change of areca on the morphology, structure, distribution of ICC andthe relationship between ICC and the enteric nerves system in the spleen and stomachQi-stagnation mouse.3. To investigate the change of areca on ICC and nitric oxide synthase (NOS) in thespleen and stomach Qi-stagnation mouse, and to explore the mechanism of areca topromote gastrointestinal motility.Methods:1. To establish mouse model of spleen and stomach Qi-stagnation:60adult ICR micewere randomly divided into control group (NS) and five licorice (GC) groups, n=10.GC group mice were treated with different concentrations of licorice solution (5,10,15,20,25g/kg) by intragastric administration, and NS group mice given equalvolume NS solution, for10days. The average daily food intake (ADFI) and waterintake (ADWI) of every group were recorded every day, small intestinal propulsionrate (SIPR) and gastric emptying rate (GER) were determined by the phenol redmethod.2.60adult ICR mice were randomly divided into NS group (n=15) and the spleen and stomach Qi-stagnation group (n=45). The spleen and stomach Qi-stagnationgroup mice, after modeling, were randomly divided into the model control GC group,the areca (BL) group, and the mosapride (MS) group, n=15. NS group, GC group,BL group and MS group were given an equal volume of NS, NS, the areca solution(5g/kg) and the mosapride solution (0.4mg/kg) by intragastric administration daily,for15days. And then tissue of mice colon in every group were observed withconventional electron microscopy, including their ultrastructure, distribution of ICCand the relationship between ICCand the enteric nerves.3.60adult ICR mice were randomly divided into NS group (n=15) and the spleenand stomach Qi-stagnation group (n=45). The spleen and stomach Qi-stagnationgroup mice, after modeling, were randomly divided into the model control GC group,the BL group, and the Nω-nitro-L-arginine methyl ester group (L-NAME), n=15. NSgroup, GC group, BL group and L-NAME group were given an equal volume of NS,NS, the areca solution (5g/kg) and the Nω-nitro-L-arginine methyl ester solution(0.4mg/kg) by intragastric administration daily, for15days. The area changes ofc-kit+and nNOS+cells from the four group colon were observed byimmunohistochemical method.Result:1. Lower-dosage groups had inhibiting effect on the ADFI, ADWI, SIP and GE, whilehigher-dosage had stimulative effect. For the ADFI and SIPR, the difference betweenthe experimental groups (5,10,25g/kg) and the NS group was significant (P<0.05).For the ADWI, the difference between the experimental groups (5,10g/kg) and theNS group was significant (P<0.05). As for the GER, the difference between theexperimental groups (5,20,25g/kg) and the NS group was significant (P<0.05).2. The NS group of ICC were characterized by long processes, large oval nuclei and scant perinuclear cytoplasm. The cytoplasm contained numerous mitochondria，abundant smooth and rough endoplasmic reticulum. ICC of GC group stretched outshorter protrusions, cytoplasm and organelles decreased, mitochondrial vacuolization,mitochondria blurred, endoplasmic reticulum expanded, incomplete part of thenuclear membrane as compared with the NS group. While the BL group and MSgroup of ICC stretched out longer protrusions, the cytoplasm of mitochondria,endoplasmic reticulum and ribosome increased. The NS group of ICC in the circulaurmuscle layer and longitudinal muscle layer of mice colon formed synaptic-likecontacts and their processes were often associated with neighboring nerve trunks. Thesynapse-like connections between GC group of ICC and neighboring nerve axonswere destroyed, and nerve fiber structure were fuzzy. And then the surroundingaxons synapse-like connection between the BL group and MS group of ICC andneighboring nerve axons were increased.3. Compared with the NS group, the c-kit+cell area of GC group and L-NAME groupmice colon were significantly reduced (P<0.01). Compared with GC group, the c-kit+cell area of the BL group mice colon was significantly increased (P<0.01). ThenNOS+cell area of L-NAME group compared with the other three groups weresignificantly different (P<0.01), while no significant difference between the NS, GC,BL three groups.Conclusion:1. There are decrease of verage daily food intake, water intaked, small intestinalpropulsion and gastric emptying in mice of licorice (5g/kg) induced spleen andstomach Qi-stagnation. Basically, this mouse model conforms to clinic andpathophysiology of spleen and stomach Qi-stagnation.2. ICC has a unique ultrastructure characters, and change the special relationship between ICC and the enteric nervous system may be the basis of areca regulategastrointestinal function.3. Areca has a repairing effect on damaged ICC of the spleen and stomachQi-stagnation mice, which may be one of the mechanisms of areca can promotegastrointestinal motility.