OBJECTIVETo observe the anti-remodeling effect of acupuncture on asthma and to explore the mechanism of T-type calcium channel protein in airway smooth muscle cell in airway remodeling effect in asthma.

METHODSThirty-two rats were randomly divided into a normal group, a model group, an acupuncture group and a sham acupuncture group, 8 rats in each group. The rats in the latter three groups were sensitized for consecutive 14 days by single peritoneal injection of aqueous suspension 1 mL of 10 mg ovalbumin (OVA), 200 mg aluminum hydroxide and saline together with 1 mL inactivated pertussis vaccine. From the 15th day, asthma was induced for 30 minutes by ultrasonic atomizing inhalation of 1% OVA for consecutive 14 days in the model group. The acupuncture group was treated with acupuncture at "Dazhui" (GV 14), "Fengmen" (BL 12) and "Feishu" (BL 13) for 30 minutes before the ultrasonic atomizing inhalation, once every two days for consecutive 14 days. The same acupoints selection and the course of treatment as the acupuncture group were produced in the sham acupuncture group and they were treated with acupuncture at 1 mm acupoint skin without retaining needles. The normal group remained unhandled. The respiratory function and the airway remodeling were evaluated by airway resistance and pulmonary histopathology, respectively, and the T-type calcium channel protein expression of Ca(v)3.1, Ca(v) 3.2, Ca, 3.3 in airway smooth muscle cell were detected by immunohistochemistry technique.

RESULTS(1) The airway resistance in the model group was higher than that in the normal group and in the acupuncture group (both P < 0.05), and the airway resistance in the acupuncture group was lower than that in the sham acupuncture group (P < 0.05). (2) The ratios of the airway wall thickness to the basement membrane perimeter (Awt/Pbm) and the airway outer perimenter to the airway internal perimeter (Po/Pi) in the model group were higher than those in the normal group and in the acupuncture group (all P < 0.05), and the ratios of Awt/Pbm and Po/Pi in the acupuncture group were lower than those in the sham acupuncture group (both P < 0.05). (3) The average optical of Ca(v) 3.1 and Ca(v) 3.2 in airway smooth muscle cell in the model group were higher than that in the normal group and in the acupuncture group (both P < 0.05), and the average optical of Ca(v) 3.3 in airway smooth muscle cell in the model group was higher than that in the normal group (P < 0.05) and it was lower than that in the sham acupuncture group (P < 0.05).

CONCLUSIONAcupuncture can inhibit the airway remodeling and the accrementition of the airway smooth muscle and can reduce the airway resistance. The mechanism may be related to the inhibition of T-type calcium channel protein in airway smooth muscle cell, especially in relation to the protein expression of Ca(v) 3.1.