In a recent investigation, Langevin and collaborators found an 80% of correspondance between the acupoints and the plane location of intra and intermuscular connective tissue in sections of post mortem tissues.  They also found that by puncturing an acupoint the needle goes through different tisular structures in comparison with the non-acupoints.  Histologically, by puncturing an acupoint the dermis and the subcutaneous tissue are pierced first, followed afterwards by the deeper fascia or conective interstitial tissue.  On the other hand, by puncturing a non-acupoint the needle pierces the dermis, the conective tissue and then encounters bone or muscle, with less possiblilities of getting through or inserting itself into the deep layer of the fascia.   Passing through the conective tissue of the deep fascia can provide an effect on the tissues known as "coiled around the needle".  It is not known exactly how this phenomenon affects acupunctural treatment.  However, acupuncturists with experience often find that rotating the needle manually generates a local tisular resistance around the needle, which can be easily felt.  Investigators have discovered that this resistance is due to, at least partially, to the traction that the needle puts on the surrounding tissues. This "coiling" phenomenon is visible through ultrasound and is translated as the "gripping force" that prevents the needle from being removed -the ancient Chinese recognized this phenomenon as "De Qi" meaning "the arrival of Qi" to the particular acupoint-. A larger force of traction or resistance is observed in the subcutaneous tissue and the fascia of the acupoints than in the subcutaneous tissue of the non-acupoints alone.  This coiling phenomenon between the needle and the conective tissue can lead to the development of sensorial signals through mechanical transduction.  It is stated that these sensorial signals coming from the stimulation of the acupoints can induce effects that include the expression of some genes, the synthesis of proteins, modifications in the extracellular matrix and other bio-physiological changes. The changes in the extracellular matrix that surround the needle may influence the other structures shared by such matrix, such as the afferent sensitive nerves, fibroblasts, vascular cells and immunological cells.  Therefore, to puncture an acupoint (in comparison to a non-acupoint) will have a greater probability of creating mechanical signals and their consequential bio-physiological effects.

Studies have also been made to determine the differences in the physical properties of the acupoints and the non acupoints, and it has been discovered that the acupoints possess a significantly higher cutaneous temperature and present a lower electrical resistance in comparison with the non-acupoints.  In later studies it was determined that the diameter of these low electrical resistance points in the skin is from 1 to 2 mm and that their distribution is similar to the classic acupoints.  A greater conductivity has also been reported in the skin of the acupoints, however, it remains unknown what it is exactly that contributes to these differences in the electrical properties of the acupoints and the non-acupoints.