As an important method in the traditional Chinese medicine, moxibustion is featured mainly with the “warm” advantage, by which it carries out stimulation at the Acupoint or the lesions and works by “stimulation from the outside and regulation from the inside”. The skin is the direct action site of moxibustion stimulation; selection of appropriate warm thermal stimulation to local skin, characteristics of responses to stimulation, and activation of relevant regulating mechanisms are based on the biological characteristics of skin, that is to say, to explore the effect law and action mechanism of moxibustion, attention has to be paid to the action characteristics of moxibustion and the characteristics of the action object of moxibustion. Modern neurobiological studies have demonstrated that [
Healthy male SD rats of clean grade, with body weight of 280–380 g, Certificate no. SCXK (Shanghai) 2007-0005, were purchased from Shanghai Slac Laboratory Animal Co., Ltd. and bred in batches. The experiment was carried out in 1 week after the rats were accommodated. The rats were divided into the following groups by the random number table: Model Control Group, Moxibustion Group 1, and Moxibustion Group 2. The number of rats in each group would support to obtain 8 complete data successfully. During the experiment, the animal treatment measures were in strict accordance with the regulations in the
Moxa strips for animals (in the diameter of 7 mm, Nanyang Chinese Medicine Moxa Company), thermostatic operating table for animals (ST-1 model, Chengdu Instrument Factory), multichannel physiological signal acquisition system (RM 6240 model, Chengdu Instrument Factory), temperature measuring device (HC-04 model, Hangzhou Hongchang Technology Company), microsyringe pump (ALC-IP800, Shanghai Alcott Biotech Co., Ltd.), full automatic tissue processor (TP1020, German LEICA Company), paraffin slicing machine (RM2145, German LEICA Company), optical microscope (BX60, Japanese OLYMPUS Company), and video camera (DP71 Image Acquisition System, Japanese OLYMPUS Company) were used.
Fast a male SD rat overnight for 12 hours, with free access to water, weigh the rat, carry out anesthesia of the rat with 20% urethane (ethyl carbamate) in the dose of 1 g/kg body weight, fix the rat in the thermostatic operating table for animals, and connect with the electrocardiograph and the temperature transducer (via the anus of the rat); once the electrocardiogram and body temperature of the rat are stable (37°C), carry out intubation in the left ventricle, as well as in the femoral artery and femoral vein of the right lower limb, to measure left ventricular pressure and arterial pressure, and administer the drug intravenously. Model control group 10 minutes after the operation, if the measurement indexes are stable, start recording data; 5 minutes later, rapid inject 0.4% inderal (4 mg/kg) via the femoral vein; then slowly inject intravenously to maintain inderal at the dose of 0.25 mg/kg/min with the microsyringe pump for 60 min, to establish the bradycardia model; no any other interventions are carried out. Moxibustion group 1: establish the model as described in the model control group. At 20 min during administration of inderal at the maintenance dose, ignite the customized slender moxa strip (20 cm long and in the diameter of 7 mm), carry out moxibustion directly to stimulate at the Ximen(PC4) Acupoint in the left upper limb of the rat for 10 min, place the probe of the temperature controller at the surface of the skin at the acupoint for moxibustion to monitor real-time temperature, and control the temperatures in the local skin for moxibustion at 38°C ± 1°C (Figure
Sample curve picture of the point skin temperature during hot stimulation process of moxibustion group, Moxibustion Group 1 (a), Moxibustion Group 2 (b).
The data are expressed as mean ± standard deviation
During the experiment, all deaths due to anesthesia, operative accidents, or drug administration, and so forth, as well as all abnormal responses to intervention of the established model, are not included for observation; 8 valid experimental cases were obtained in each group, so a total of 24 cases were obtained.
Statistical analysis was carried out by the 5 min means for each of the indexes collected, such as HR, MAP, and cardiac function (LVSP, +dp/dtmax, and t-dp/dtmax). To reduce any statistical errors due to individual differences, the changes before and after intervention in each experimental animal were expressed in percent: Change Rate (%) = (value after intervention − value before intervention)/value before intervention × 100%. The results were provided as follows.
The administration of inderal resulted in rapid decrease of HR and MAP in rats (on average, in 60 minutes, HR was decreased by 34.98% ± 5.86%, and MAP was decreased by 33.21% ± 5.63%). In 20 minutes after administration of inderal, the model was stable successfully; during 40-min maintenance after 20 min administration of inderal, the mean change rate of HR was −0.16% ± 1.98% and that of MAP was 0.37% ± 2.09%. The results showed that the method was able to establish brachycardia rat models with stable effects (Table
Mean change percentage of the model group HR, MAP (%).
Model group |
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HR | MAP |
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60 minutes after administration of inderal | 8 |
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After 20-min administration of inderal | 8 | − |
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After the model was established successfully with inderal, the waveforms of left ventricular pressure and arterial pressure were obviously decreased than normal; after thermal stimulation by moxibustion at 38°C and 46°C, the waveforms of left ventricular pressure and arterial pressure were recovered to some extents than those in the model (Figure
Sample waveshape picture of the LVP, AP of each group: normal condition (a), the model was established successfully with inderal (b), after thermal stimulation at 38°C (c), after thermal stimulation at 46°C (d).
Compared with those in the model control group, the thermal stimulation in the Moxibustion group 1 was able to increase HR, MAP, LVSP, and +dp/dtmax and reduce t-dp/dtmax in rats; however, the effects were not significant (
Mean change percentage of the HR, MAP, LVSP, +dp/dtmax, and t-dp/dtmax of different groups after moxibustion treatment.
Group |
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HR (/min) | MAP (mmHg) | LVSP (mmHg) | +dp/dtmax (mmHg/s) | t-dp/dtmax (ms) |
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Model control group | 8 |
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Moxibustion group 1 | 8 |
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Moxibustion group 2 | 8 |
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Analysis of variance | ||||||
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10.660 | 14.963 | 13.875 | 13.568 | 7.217 | |
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0.001 | 0.000 | 0.000 | 0.000 | 0.004 |
Note: the values in the table for each index value variation rate.
Compared with model control group *
Compared with moxibustion group 1
The morphology of mast cells was observed under the 10 × 40 optical microscope, and mast cells with degranulation in skin were counted.
Findings of mast cells in slices of skin tissues in the area of the Ximen Acupoint were observed under optical microscope. (1) Model control group: the mast cells were of smooth cell walls and of complete morphology (Figure
Morpohologies of Mast cells in the Local Site of the Ximen Acupoint: Model Control Group (a), Moxibustion Group 1 (b), Moxibustion Group 2 (c).
The criteria for counting mast cells with degranulation were: count as 1 when the mast cell was with ruptured cell wall, and there were scattered granules in the matrix. Degranulation rate = count of mast cells with degranulation/total count of mast cells × 100%. The mean of degranulation rates from 4 slices which were closest to the local site of moxibustion was calculated in each tissue sample, add the mean of degranulation rates of this group all tissue samples together, and divided by the number of samples in each group, then the degranulation rate of mast cells could be calculated.
If no intervention was carried out to the skin at the Ximen Acupoint in rates, the degranulation rate in the local site was as lowas 12.9%; after thermal stimulation bymoxibustion, the degranulation rate of mast cells was significantly increased
Degranulation rate of mast cells.
Group |
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Degranulation rate of mast cells % |
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Model control group | 8 |
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Moxibustion group 1 | 8 |
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Moxibustion group 2 | 8 |
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Note: compared with model control group
compared with moxibustion group 1 ▲
From ancient times, moxibustion is one of the important methods in treatment of cardiovascular diseases in clinical practices. It is a crucial problem for moxibustion research how to objectively assess the effects of moxibustion on heart and blood vessels, to explore the possible mechanism for differences of effects, resulted from stimulation by moxibustion at different temperatures as an influencing factor, and to provide a basis for optimizing the clinical operating program of moxibustion. In this experiment, propranolol, a
The ancient doctors emphasis moxibustion heat stimulates the skin local inflammatory response is beneficial to the treatment of diseases. Our study demonstrated that the thermal stimulation by moxibustion may influence the morphology of mast cells in the local site of moxibustion, promote their degranulation, and similarly, the thermal stimulation by moxibustion at 46°C is obviously stronger than that by moxibustion at 38°C. The results suggested that higher or lower mast cell degranulation rate influenced the improvement of cardiac function, so the characteristics of warm thermal stimulation by moxibustion are certainly associated with the effects on the target organ, as well as on the local site of moxibustion. The local site of moxibustion is the direct object of moxibustion action, and is one of the key links for the starting mechanism of the moxibustion effects. The therapeutic effect of moxibustion is to regulate the body by stimulating the acupoints, while the regulating effects are dependent on receptors in the acupoint area. Recent studies have believed that the skin is an important neuroendocrine organ, which may synthesize and secrete many neurotransmitters and peptide substances [
In this study, the relevant new biological knowledge of the skin was used as the basis for this study, to focus on differences of the effects due to warm thermal stimulation by moxibustion at different temperatures and to explore their association with physiological feedback responses from different thermoreceptors in the body. This was because that, during the previous research on the action mechanism of moxibustion, we paid more attention to the effects of moxibustion therapy on the diseased target organ and overlooked the unique path and mechanism of starting effects by moxibustion on the target organ. Every effective therapeutic measure may produce effects on the target organ, and the specificity of its action path is the important basis for existence of the method. Based on the stimulation-response process of thermal stimulation by moxibustion → local reception → temperature → chemical conjugation linkage → biological information cascade reaction → effect realization [
Arterial pressure
Maximum rate of left ventricular pressure rise
Heart rate
Left ventricular systolic pressure
Mean arterial pressure
Mast cells
Transient receptor potential
Transient receptor potential vanilloid subfamily member 1
Time from the beginning of left ventricular systole to the maximum rate of left ventricular pressure rate.
This present study was supported by the National Key Basic Research Program (NKBRP): 2009CB522905, funded by MOST of China.