Objective To observe the effect of acupuncture on serum IgE level

the degranulation of mast cells

the release of histamine and serotonin

and the expressions of phosphorylated tyrosine-protein kinase Lyn and Syk(p-Lyn

p-Syk) in skin tissue in rats with urticaria

as well as analyze the mechanism of acupuncture in the prevention and the treatment of urticaria. Methods SD male rats were randomly divided into normal control

model control

medication and acupuncture groups(n=10 in each group). The anti-ovalbumin serum was used to establish urticaria model. Rats of the medication group received gastric lavage of Loratadine(0.1 mg/100 g). In the acupuncture group

bilateral "Xuehai"(SP10) and "Quchi"(LI11) were punctured perpendicularly

about 2 to 4 mm in depth

and the needles were retained for 30 min. The treatment was given consecutively for 14 days in the two treatment groups. H.E. staining was adopted to observe the morphological changes of skin tissue

ELISA to determine the total IgE level in serum

the toluidine blue staining to observe the degranulation of mast cells in local skin tissue and the immunohistochemistry to determine the expressions of histamine and serotonin as well as the the expressions of p-Lyn and p-Syk. Results Compared with the normal control group

the epidermis of the model control group was significantly thickened

the dermis was swollen

the inflammatory infiltration of small vessels was serious and the mast cells were swollen and deformed

with blurred edge and exfoliated granules. Additionally

in the model control group

the serum IgE level was significantly higher(P<0.05)

the expressions of histamine and serotonin

as well as p-Lyn and p-Syk proteins in local skin tissue were significantly increased(P<0.05). Compared with the model control group

in the acupuncture group and the medication group

the epidermis was slightly thickened

the dermis got slightly edema

the inflammatory cells were presented occasionally and the degranulation of mast cells were reduced. Besides

the serum IgE level was significantly decreased(P<0.05)

the expressions of histamine and serotonin

as well as the p-Lyn and p-Syk were significantly reduced(P<0.05). There was no significant difference in each index between the acupuncture group and the medication group(P>0.05). Conclusion Acupuncture at LI11 and SP10 is applicable in the treatment of urticaria. This therapy inhibits the type Ⅰ hypersensitivity and the mast cell degranulation

which may be related to the regulation of p-Lyn and p-Syk protein expressions in the locus coeruleus skin tissue.