Objective: To calculate the imbalance degree (IBD) of left-right meridian (IBD-LRM), IBD of exterior-interior meridian (IBD-EIM) and IBD of hand-foot meridians (IBD-HFM) of impedance in extracellular fluid of cells in twelve meridians of healthy subjects, so as to provide foundation for meridian diagnosis.
Methods: A total of 31 healthy volunteers were enrolled and bioelectrical impedance spectroscopy (BIS) was applied. The constant current (from 1 to 100 kHz, 200 μA) was connected into the bilateral twelve meridians through two excitation electrodes with a distance of 10 cm. Two measuring electrodes, with an interval of 5 cm, were set in between the two excitation electrodes to collect the voltage amplitude and phase. The Cole-Cole curve fitting was used to calculate the impedance of extracellular fluid of cells in the twelve meridians; the IBD-LRM, IBD-EIM and IBD-HFM as well as their absolute values were calculated.
Results: The impedance of extracellular fluid in the left side was higher than that in right side in the large intestine meridian, the small intestine meridian and the bladder meridian (P<0.05, P<0.01). The mean value of IBD-LRM of extracellular fluid was (4.0±1.4) %; the mean value of absolute value of IBD-LRM was (15.0±1.1) %; the maximum absolute value of IBD-LRM was the bladder meridian. The mean value of IBD-EIM was (3.3±1.0) %; the mean value of absolute value of IBD-EIM was (17.9±1.6) %; the maximum absolute value of IBD-EIM was the bladder meridian and the kidney meridian. The impedance of extracellular fluid of hand jueyin meridian, hand taiyin meridian and hand shaoyin meridian were lower than those of foot meridians. The mean value of IBD-HFM was (-2.6±1.1) %; the mean value of absolute value of IBD-HFM was (19.7±1.7) %; the maximum absolute value of IBD-HFM was shaoyang meridian; the imbalance of yin meridians was greater than yang meridians. There were significant differences in impedance of extracellular fluid between left and right and between hands and feet (P<0.05, P<0.01).
Conclusion: The extracellular fluid of left-right meridians of healthy subjects is different, but the absolute value of IBD is low; the mean value of exterior meridian and interior meridian is very close, and the absolute value of IBD is medium; the impedance of the foot meridians are greater than the hand meridians, and the absolute value of IBD is relatively high.
Keywords: bioelectrical impedance spectroscopy (BIS); exterior-interior meridians; imbalance degree (IBD); meridians with the same name; twelve meridians.