The skin impedance has been used as an index to plot out the meridian courses.In most of this kind of methods during measurement voltage was ne- cessary to deliver to the subject's skin.It is unknown whether increasing the measuring voltage can change non-low skin impedance points (non-LSIP) into low skin impedance points (LSIP).In order to clarify the problem

we made an investigation on the effect of increasing and decreasing the measuring voltage on skin impedance. Subjects under observation were 12 healthy volunteers.On the medial side of forearm two levels were selected for measurement.Four or twenty non- LISP were observed on each level.The measuring system worked on the basis of bielectrode method.The measurement and data processing were controlled by microcomputer.During measurement impedance of LSIP decreased correspo- ndingly with the increase of voltage and vice versa

but the value of impedance was not exceeded 100kΩ in spite of increasing or decreasing the voltage.That is

low impedance is the inherent characteristics of LSIP.On the contrary

the impedance of non-LSIP remained in higher than 600kΩ in most of cases during increasing voltage from 10 to 50v.As the voltage increased to 65v

the impe- dance in a part of non-LSIP decreased to such a low level as LSIP.However

thier impedance increased rapidly to high level again once the measuring voltage decreased.The above results reveal that the response of non-LSIPs and LSIPs were different from each other in nature.Increasing the voltage could not cha- nge a non-LSIP into LSIP.The difference between the two was not caused by the measurement errors

but really a biological phenonmenon.