Although some important progresses were made in the field of the meridian research, no breakthroughs have been achieved. Besides,there are some problems in meridian researches. Particularly, previous research of meridian phenomenon involved lots of subjective elements and outcomes.Researches that use modern scientific techniques to investigate the biological characteristics of meridians are urgently needed. Therefore, this study is designed to assess the metabolic characteristics of the Heart and Lung meridians by using functional near infrared spectroscopy. Thus, the biological characteristics of meridians could be presented objectively in a scientific methodology.

The Lung and Heart meridians are chosen as two specific studied meridians. Participants of chronic obstructive pulmonary disease (COPD) and healthy volunteers will be enrolled.

120 participants will be included and divided into the healthy control group, chronic obstructive pulmonary disease (COPD) group and healthy intervention group. Functional near infrared spectroscopy will be used to assess the metabolic characteristics of the Heart and Lung meridians. The specificity for the meridian-visceral association will be investigated by comparing the metabolic difference between the Heart and Lung meridians in the healthy control group and COPD group. Besides, participants in the healthy intervention group will receive two sessions of moxibustion in the Heart meridian and Lung meridian respectively to explore the specificity for the site-to-site association.

Inclusion Criteria:

Inclusion criteria for COPD

1. Patients should meet the above diagnostic criteria, and the severity of COPD is in the stage of GOLD 2 or 3 based on pulmonary function testing;
2. COPD patients in the stable phase, who present with mild symptoms of cough, expectoration and short breath;
3. 35 ≤ age ≤75 years, male or female;
4. Patients have clear consciousness and could communicate with others normally;
5. Patients could understand the full study protocol and written informed consent is signed by themselves or their lineal kin.

Inclusion criteria for health volunteers

1. Healthy volunteers who could provide a recent medical examination report to confirm they have not any cardiovascular, respiratory, digestive, urinary, hematological, endocrine and neurological disease;
2. Age≥20 years, male or female;
3. Participants have clear consciousness and could communicate with others normally;
4. Participants could understand the full study protocol and have high adherence .Written informed consent is signed by themselves or their lineal kin.

Exclusion Criteria:

Exclusion criteria for COPD

1. Patients who fail to meet the diagnostic criteria for COPD, or COPD patients in the phase of acute exacerbation;
2. Patients have the following complications, which includes pneumonia, bronchial asthma, bronchiectasis, active tuberculosis, pneumothorax, chest trauma, tumors of the lung or thorax, and other confirmed respiratory diseases;
3. Patients have concomitant conditions of heart diseases, such as chronic stable angina pectoris;
4. Patients have serious concomitant conditions and fail to treat them effectively, such as diseases of the digestive, urinary, respiratory, hematological, and nervous system;
5. Patients have mental illness, severe depression, alcohol dependence or history of drug abuse;
6. Pregnant or lactating patients;
7. Patients are participating in other trials.

Exclusion criteria of health volunteers

1. Participants have sudden severe diseases during the trial, such as cardiovascular diseases, liver diseases, kidney diseases, urinary diseases and hematological diseases.
2. Participants have mental illness, severe depression, alcohol dependence or history of drug abuse;
3. Pregnant or lactating participants ;
4. Participants are participating in other trials.