Abstract: BACKGROUND: Heat-sensitive moxibustion is widely used in clinical treatment and basic research, but the biological characteristics of its sensitized acupoints are not completely clear.
OBJECTIVE: To explore the effects of heat-sensitive moxibustion on connective tissue, calcium and terahertz wave in psoriatic rats and the relationship between them.
METHODS: Animal models of psoriasis were induced by 5% imiquimod cream in Sprague-Dawley rats, and the experimental rats were randomly divided into blank group, model group and treatment groups. Except the blank group, the rats in the other groups were modeled with psoriatic lesions on the back and along the Sanjiao meridian of hand-Shaoyang. After successful modeling, the treatment group was treated with moxibustion at Waiguan acupoint at the same time every day, 40 minutes once for 7 days in total. During the treatment period, the tail temperature changed > 1 oC was considered to be the heat-sensitive moxibustion group, and the tail temperature changed ≤ 1 oC was considered to be the moxibustion group. Hematoxylin-eosin staining was used to observe the pathological changes of subcutaneous connective tissue, colorimetric method was used to detect the changes of calcium ions in subcutaneous fascia, and terahertz wave detector was used to detect the changes of mean terahertz wave voltage at Waiguan point.
RESULTS AND CONCLUSION: Compared with the blank group, the pathological changes of connective tissue were obvious in the model group. Compared with the blank group and model group, the calcium ion concentration in subcutaneous fascia was significantly higher in the moxibustion group and heat-sensitive moxibustion group (P < 0.01). The calcium ion concentration in the subcutaneous fascia was significantly higher in the heat-sensitive moxibustion group than the moxibustion group (P < 0.01). On the 3rd day of treatment, the mean terahertz wave voltage values in the treatment groups were higher than those in the model group and the blank group (P < 0.01). On the 7th day, the mean terahertz wave voltage in the moxibustion group was still higher than that in the model group and the blank group (P < 0.01), while the mean terahertz wave voltage in the heat-sensitive moxibustion group was close to that in the blank group. Compared with the moxibustion group, the mean terahertz wave voltage of the heat-sensitive moxibustion group was increased significantly on the 3rd day (P < 0.01) and decreased significantly on the 7th day (P < 0.01). To conclude, during the treatment with heat-sensitive moxibustion, local calcium ions are enriched in the acupoint of psoriatic rats, and terahertz waves are also changed. There may be a close link between heat-sensitive moxibustion, calcium ions and terahertz waves to treat or improve the symptoms of psoriasis.

Key words: heat-sensitive moxibustion, psoriasis, connective tissue, calcium ion, terahertz wave, model rat