Objective:To search the impact of helicobacler pylori infection in changes of mice gastric mucosa mast cells and degranulation process

therefore to establish the important role of Hp in the pathogenesis of chronic urticaria.Methods:50 BALB/c healthy mice were randomized into two groups:Hp group

consist of 30 mice

were given Hp liquid every 3 days for total 7 times.Bovine albumin serum(BAS)as control group

was given BAS 2% with the same way as Hp group.Toluidine blue staining of the gastric mucosa was used to assess the total number of mast cells

the amount of degranulated mast cells and the percentage of degranulation after feeding.Each slide was cnnseeutive count with 10 high-power fields for mast cells; results express with number of mast cells/high power field

the ratio of degranulated mast cell was expressed by the amount of degranulated mast cells/total of mast cells.At the same time compared with the control group.Results:There was significant statistical difference in the total number of mast cells between the tow groups(100.0vs0.7

P<0.01);total degranulated mass cells among two groups had a statistic significant different(48.85vs6.51

P<0.01);degranulated mast cell percentage among two groups had a statistic significant different(50%vs23%

P<0.01).Conclusion:Hp infection increases the number of gastric mu- cosa’mast cells

also significantly increases degranulated mass cells proportion

thus release histamine and a series of vascular activation transmitter to peripheral circulation that may cause a vascular mucosa dilation

wheal

etc.A typical urticaria sign.