[Effect of mild-warm moxibustion on microcirculation in the raw surface tissue of chronic refractory wound in skin ulcer rats].

OBJECTIVE: To observe the effects of mild-warm moxibustion on dynamic blood flow, microvessel count (MVC)and vascular endothelial growth factor (VEGF) expression in the wound tissue of the chronic skin ulcer in rats, so as to reveal its underlying mechanism in promoting wound recovery. METHODS: A total of 104 male SD rats with skin injury were randomly divided into control group (n=8), model group (n=32), TDP (far-infrared heating device) group (n=32) and moxibustion group (n=32). Chronic refractory raw surface wound model was established by muscular injection of Hydrocortisone Sodium Succinate. For rats of the TDP and moxibustion groups, TDP irridiation and mild-warm moxibustion were applied to the raw surface, bilateral "Shenshu" (BL 23) and "Zusanli" (ST 36) for 15 min, once daily for 3, 7 and 14 days respectively. The healing rate and the healing time of raw surface of the wound were observed. The blood flow of the raw surface of the wound tissue was measured by laser Doppler flowmeter and the MVC in granulation tissue of chronic skin ulcer was counted under light microscope. VEGF expression was detected by immunohistochemistry. RESULTS: In comparison with the control group, the healing rate of the wound raw surface was significantly lower and the healing time was prolonged in the model group (P < 0.01). Compared with the model group, the healing rates on day 3, 7, 10 and 14 were significantly higher and the healing time was strikingly faster in both TDP and moxibustion groups (P < 0.01, P < 0.05), and the effects of the moxibustion group in increasing the healing rate and shortening the healing time were significantly better than those of TDP group (P < 0.01). In comparison with the model group, the blood flow volume, MVC and VEGF expression levels on day 3 and 7 were upregulated significantly in both TDP and moxibustion groups (P < 0.01, P < 0.05); while the blood flow volume, MVC and VEGF expression level in the moxibustion group and the blood flow volume and VEGF expression level in the TDP group downregulated considerably on day 14 (P < 0.01). No significant difference was found between the TDP and moxibustion groups in the MVC on day 14 after the treatment (P > 0.05). CONCLUSION: Mild-warm moxibustion can promote wound healing, which is closely with its effects in increasing blood flow and MVC, and upregulating VEGF expression in the wound granulation tissue of the chronic skin ulcer.