[Effects of different quantity of moxibustion at "Dazhui" (GV 14) on cellular immunity in asthma rats]

To observe the effects of different quantity of moxibustion of "Dazhui" (GV 14)on the levels of serum interleukin-4 (IL-4), interferon-gamma (IFN-gamma), and immunoglobulin E (IgE) in asthma rats, so as to reveal its mechanisms underlying immune regulation.

Sixty male SD rats were randomly divided into control, model, moxibustion-15 min (M-15 min), M-30 min, M-60 min, and M-120 min groups (10 rats/group). Asthma model was established by intraperitoneal injection of sensitized-suspension (containing egg albumin, aluminium hydroxide, and deactivated Bacillus pertussis) and ovalbumin-aerosol inhalation. Moxibustion was applied to "Dazhui" (GV 14) for 15, 30, 60 and 120 min, respectively. Serum IL-4, IFN-gamma and IgE contents were assayed by ELISA (enzyme-linked immunosorbent assay).

Compared with the control group, serum IL-4, IFN-gamma and IgE levels were increased significantly (P<0.01), and serum IFN-gamma/IL-4 level was down-regulated obviously (P<0.01)in the model group. After the moxibustion treatment, the levels of serum IL-4 and IgE in the M-15 min, M-30 min, M-60 min, and M-120 min groups were reduced significantly compared with the model group (P<0.01, P<0.05). The ratios of IFN-gamma/IL-4 in the M-15 min, M-30 min, M-60 min, and M-120 min groups were significantly higher than that in the model group (P<0.05, P<0.01). Comparison among the M-15 min, M-30 min, M-60 min, and M-120 min groups showed that the therapeutic effects of the M-30 min group were evidently superior to those of the M-15 min group, and those of the M-60 min group were significantly superior to those of the M-30 min group in lowering serum IL-4 and IgE contents and up-regulating IFN-gamma/IL-4 (P<0.05, P<0.01). No significant differences were found between the M-60 min and M-120 min groups in down-regulating IL-4 and IgE levels, and in raising IFN-gamma/IL-4 level, as well as among the M-15min, M-30 min, M-60 min and M-120 min groups in elevating serum IFN-gamma levels (P>0.05).

Moxibustion can restrain the secretion of IL-4, relieve the inflammatory reaction of IgE, and enhance the ratio of IFN-gamma/IL-4 in asthma rats, which presents an increase tendency of the curative effect along with the extension of the treatment time from 15 min to 60 min. Excessively long time (>60 min)of treatment is not necessary.