Serum from asthmatic rat treated with acupuncture inhibits acetylcholine- induced contractile responses of airway smooth muscle cells

To investigate the influence of serum from asthmatic rat treated with acupuncture (acupuncture serum) on the contractile responses of airway smooth muscle cells (ASMCs). OVA-induced asthmatic rats were subject to acupuncture treatment at the points of Dazhui (GV 14), Fengmen (BL 12), and Feishu (BL 13). The resulting serum was collected, as well as serum from normal animals. Contraction of ASMCs was induced with 10 μM acetylcholine (Ach), and acupuncture serum or normal serum was supplemented 15 min later. The effects of the sera on the changes in cell length, width, and surface area were monitored in real time via a live cell imaging system. The contraction rates of ASMCs 15 min and 30 min after Ach stimulation reached 38.2% ± 3.8% and 49.7% ± 4.6%, both of which were significantly higher than unstimulated control cells (P < 0.01). Acupuncture serum at the 1:100 dosage reduced the contraction rate of ASMCs from 40.1% ± 5.1% to 17.6% ± 6.5% (P < 0.01). Thus, the treatment significantly inhibited the Ach-induced contractile responses of ASMCs and yielded a relaxation efficiency of 58%, which was greater than the effects obtained with a 1:250 dosage. Treatment with acupuncture serum at 1:500 dosage or normal serum displayed no clear effect of suppressing Ach-induced contraction of ASMCs. Our data suggest that acupuncture serum has the effect of inhibiting Ach-induced contraction of ASMCs, thereby promoting relaxation of the cells.