Objective:To explore the mechanism of the formation of infrared radiant track along meridian course(IRRTM). Methods:The oxygen partial pressure in 5 acupoints Yaoyangguan (GV 3)

Mingmen (GV 4)

Zhongshu (GV 7)

point below T 8 process and Shenzhu (GV 12)along Du Meridian and the bilateral control points 2.5 cm to Du Meridian (5 levels) were taken to be observed in twenty eight volunteer subjects. At the same time

the image of infrared radiant track over the back of these subjects was recorded. Results:Besides the higher temperature infrared radiant track of Du Meridian

the oxygen partial pressure (PO 2) values in the deep tissues along Du Meridian are 8.13±0.61 kPa

7.63±0.55 kPa

8.07±0.57 kPa

6.90±0.41 kPa and 7.95±0.68 kPa

being significantly higher than those of the left and the right control points (6.30±0.53 kPa and 5.46±0.43 kPa

5.25± 0.45 kPa and 5.93±0.46 kPa

6.35±0.51 kPa and 6.18±0.50 kPa

5.48±0.46 kPa and 4.80± 0.49 kPa

and 5.85±0.57 kPa and 5.63±0.51 kPa respectively

P <0.05～0.001). The results suggest that higher PO 2 along higher temperature infrared radiant track of meridian means higher oxygen metabolism rate

which may be an important factor for the formation of IRRTM

and maybe contribute to the transformation and transmission of signals of meridians and to the regulation of functional activity of the human body.Conclusion:PO 2 is obviously higher along the higher temperature infrared radiant track of meridian.