Hypothetical experiments were done to examine various problems in the acupuncture research. Statistically significant suppressive effects of electroacupuncture (vs. control group) were demonstrated. A simple paper was made based on the hypothetical experimentation, and the insufficient descriptions, lack of experimental designs, errors in statistical methods were pointed out, then several comments were added. Several problems included in the multi-sample experimental designs and their statistical analysis in the acupuncture research were also discussed.

Effects of moxibustion on the jaw-opening reflex (JOR) were examined in lightly anesthetized rats. The evoked EMGs of digastric muscle elicited by tooth pulp stimulation were clearly suppressed for 2-3min by the moxibustion applied to the hair-removed skin. The suppressive effects of moxibustion on the JOR indicated some regional differences. The most effective region was the contralateral fore-arm, and a slightly less effective regions were the ipsilateral face, ipsilateral fore-arm and contralateral hind-leg. The difference of the effectiveness on JOR suppression between the acupuncture point and non-acupuncture point was not apparent.
These results suggest that the polymodal receptor, which is undoubtly activated by moxibustion, participates in the peripheral process of the induction of analgesic effect.

In the acupuncture clinic the method of selecting treatment points by measuring the electrical resistance of the skin has been widely used. It has become known that depending on the measuring period and the loaded voltage, the low resistance points of the skin are easily created, thus there remain many problems of the methods for measuring the skin resistance.
The present study was performed on the forearm skin of human subjects. For the measuring electrode an Ag-AgCl wire electrode with a diameter of 0.5mm was used. The electrode was fixed up to a FD-pick up (Nihon Kohden) and monitoring the pressure applied to the skin. A metal rod wrapped in a piece of gauze soaked with saline solution was used as the indifferent electrode. The skin resistance was calculated by measuring the current pass the both electrodes with a fixed resistance (10KΩ) Placed in series in the circuit when a square pulse (10msec, 4V) was appqied to the skin.
By used of the spuare pulse the low resistance points of the skin are stably detected when they are measured repeatedly. On the other hand, by of -DC 10 Volt, tce low resistance points gradually increase in number and lowering the resistance value by repeated measurerents. The sweat glands and hair follicle also show the low resistance value.
In conclusion, we could not distinguish the “true” low resistance points from sweat gland and other resistance destroyed points by measuring current clearly. But the square pulse method for measuring the skin resistance is useful to detect the low resistance point.

[Objective]Capsaicin induces flare reaction in the human skin, and repetitive capsaicin applications induce capsaicin desensitization. To investigate the receptors related to flare reaction by acupuncture and moxibustion, we measured pain thresholds and flare reaction in two areas.
[Methods]Thirteen healthy volunteers with informed consent participated in this study. Capsaicin (0.1%) was applied repetitively (6 h/3days) to the forearm skin to desensitize the area. Then, mechanical and heat pain thresholds, flare reactions that induced by acupuncture and moxibustion were measured.
[Results]In the desensitized area, the heat pain threshold was significantly increased but the mechanical pain threshold did not change. Moxibustion induced flare reaction and it was significantly diminished under capsaicin desensitization. On the other hand, acupuncture induced flare reaction and it disappeared completely under capsaicin desensitization.
[Discussion and Conclusion]These results revealed that the flare reaction induced by acupuncture and moxibustion requires TRPV1 activation. For the moxibustion, flare reaction was significantly diminished under capsaicin desensitization but remained significant. Therefore we suggest that TRPV1 mainly mediates the flare reaction but other heat sensitive receptors might be involved in flare reaction. While the mechanical pain threshold was not changed under capsaicin desensitization, flare reaction induced by acupuncture disappeared completely. This suggests that flare reaction is not induced by the mechanical stimuli of acupuncture itself, but other factors such as inflammatory mediators released from damaged cell causing flare reaction by acupuncture.

Suppressive effects of thermal stimulation of the tail on the jaw opening reflex were examined by the reversal design of single subject designs (SSD) in an urethane anesthetized rat. The results were evaluated by visual inspections of the graphs of moving averaged data and by C statistic as a simple time series analysis. The digastric evoked EMGs elicited by electrical stimulation of the gingiva (1.5x threshold intensity, 0.2Hz) had stable latency and biphasic wave form. Clear suppression of the JOR during thermal stimulation of 54°C for 30s was found by the visual inspection. The calculated C statistics based of 12 data of that of before and during thermal stimulation showed significant trends (p<0.05).
On the other hand, no significant trends were observed in baseline period and the data of 32°C thermal stimulation, and they were in agreement with the results of visual inspections.
These results indicate the noxious thermal stimulation activate the endogenous pain inhibitory mechanisms then induces analgesic effects, and the similar mechanisms were suggested to be participated in acupuncture or moxibustion stimulation-induced analgesia. Moreover the fact that evaluations by the C statistics agreed with the visual inspection suggests the validity of C statistic for evaluating the time series data in the SSD.