[Effects of Acupuncture at Zusanli on Plasma Dopamine and Lung Function of Rats with COPD]

To explore the mechanism of acupuncture in regulating chronic inflammation through dopamine in rats with chronic obstructive pulmonary disease (COPD).

32 SD rats were randomly divided into control, model, sham acupuncture and acupuncture groups (n=8) . COPD condition was induced by eight-week exposure to cigarette smoking and lipopolysaccharides (LPS) of the rats, except for those in the control group. From the beginning of the 7th week, the acupuncture group received bilateral electroacupuncture on the Zusanli (ST-36), while the sham acupuncture group received bilateral electroacupuncture on the non-points, 30 min/time, 1/day, for 2 weeks prior to exposure to cigarette smoking. Post treatment changes in plasma dopamine and inflammatory factors [tumor necrosis factor-α (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), interleukin-8 (IL-8)], lung function [total lung capacity (TLC), functional residual capacity (FRC), the 50 μs forced expiratory volume (FEV) vs. forced vital capacity (FVC)( FEV₅₀/FVC), the 100 μs FEV vs. FVC (FEV₁₀₀/FVC), total airway resistance (RL), lung dynamic compliance (Cdyn)], and the ratio of total alveolus area to tissue area (A/t) and cell counts in the alveolar lavage fluid (BALF) were measured. Pearson correlations between plasma dopamine and the above indicators were calculated.

Acupuncture increased plasma dopamine and improved the inflammatory factors, lung function, A/t and BALF cell counts. Compared with the model rats, the rats that received acupuncture had higher levels of TNF-α and IL-1β, A/t and BALF cell counts, and lung function (FEV₅₀/FVC, FEV₁₀₀/FVC, RL, Cdyn) (P<0.05). The effects of acupuncture were superior on the ST-36 points compared with the non-points. Significant correlations between lung function (FRC, RL, Cdyn) and inflammatory factors (TNF-α, IL-1β, IL-6, IL-8) were found (P<0.001) . TLC was correlated with IL-8, IL-1β and A/t (P<0.05). Plasma dopamine was correlated with FRC, TLC, FEV₅₀/FVC, FEV₁₀₀/FVC (P<0.05).

Acupuncture can alleviate inflammation, improve lung function and raise plasma dopamine level in COPD rats, and the effect of acupuncture on lung function may be related to reducing inflammatory factors and increasing dopamine level.