PHOTOPHLETHYSMOGRAPHIC CHANGES INDUCED BY SKIN STIMULATION USING ACUPUNCTURE

The photoplethysmographic signal was recorded, before and then 10 minu tes after an acupuncture stimulation, in 46 subjects divided into two groups: group A included 22 cases in which the stimulation was applied at the two classical acupoints SP-6 (Sanyinjiao) and GB-39 (Xuanzhong ), and group B included 24 cases in which the stimulation was applied outside the acupuncture zones. A highly significant increase (P<0.01) of the photoplethysmographic signal after stimulation versus the basal amplitude was observed both in group A (+215%, i.e., from 6.50+/-1.67 mm to 20.47+/-3.18mm) and in group B (+121%, i.e., from 7.35+/-1.66mm to 16.29+/-1.97mm). However, the greater increase in blood flow in gro up A versus group B, which is also statistically significant (P<0.05), indicates a supplementary specific vasoactive effect of the two acupo ints.