Effect of dexamethasone injection into Zusanli (ST 36) acupoint on ovalbumin-induced allergic rhinitis.

OBJECTIVE: To investigate the effects of acupuncture with dexamethasone (A. Dex) on allergic rhinitis (AR) by injecting dexamethasone into the Zusanli (ST 36) acupoint.

METHODS: Thirty 6-week-old female BALB/c mice were sensitized on days 1, 5, and 14 by intraperitoneal injection of 100 µg of ovalbumin (OVA). The mice were then randomly divided into six groups (n = 5 in each group). Five groups were sensitized intranasally with 2 μL of 1.5 mg of OVA for 10 consecutive days, while one group was sensitized intranasally with PBS in a similar manner as a negative control group. One hour before each administration of intranasal OVA, two groups were orally administered either a control vehicle (distilled water; AR control group) or 200 μg/kg Dex (O. Dex group), while three groups received A. Dex at Zusanli (ST 36) with Dex concentrations of 2, 20, and 200 μg/kg for each group, respectively. AR symptoms were evaluated by measuring the rubbing score, which comprised the number of nose, ear, and eye rubs that occurred in the initial 10 min after OVA intranasal provocation on the 10th day. We isolated spleen, serum, and nasal mucosal tissue after measuring the rubbing score. Spleen weight was measured using an electronic microbalance. The levels of IgE, thymic stromal lymphopoietin, tumor necro- sis factor-α, intercellular adhesion molecule-1, and macrophage-inflammatory protein-2 in serum or nasal mucosal tissue were measured using enzyme-linked immunosorbent assays. The serum histamine levels of OVA-sensitized AR mice were measured using O-phthaldialdehyde spectrofluorometry. Western blot analysis was performed on nasal mucosal tissue extracts.

RESULTS: A. Dex significantly reduced the rubbing score, spleen weight, serum IgE, and serum histamine in OVA-sensitized mice. A. Dex significantly decreased the serum levels of inflammatory cytokines (thymic stromal lymphopoietin and tumor ne- crosis factor-α) in OVA-sensitized mice. A. Dex sig-nificantly reduced the nasal mucosal levels of inflammatory markers (intercellular adhesion molecule-1andmacrophage-inflammatory protein-2) inAR mice. A. Dex effectively attenuated the expression of caspase-1 and receptorinteractingprotein-2 in nasal mucosal tissue.