The Effects of Acupuncture on Fibronectin, Collagens and Laminin in the Burn Wound Healing of Rats

Chang, Ho Jun; Woo, Bong Sik; Shin, Che Soo; Seo, Youn Kyoung; Paik, Doo Jin; Kim, Nam Soo

Abstract

The present study was performed to examine whether acupuncture can regulate the expression of extracellular matrix proteins that play important roles in burn wound healing of rat, such as fibronectin, type I and IV collagens, and laminin. Sprague-Dawley rats weighing 250~300 g were divided into 4 groups such as normal control group (C), only acupuncture treatment group (Ca), burn treatment group (B), and a group for acupuncture treatment after burn (Ba). We burned 15x25 mm in size for 15~18 seconds at lumbar area of rats with special iron adapter and acupunctured at 5~7 mm in diameter and 1 cm in depth using 0.25 mm x 50 mm acupuncture needle for 20 minutes in wound area. Rats in group Ca were acupunctured once, and rats in group Ba were acupunctured every 12 hours 3 times. Rats sacrificed at days 1, 3, 7, 15 and 20 after burn treatment. Histological changes were examined by azan staining methods and expression profiles of fibronectin, type I and IV collagens, and laminin were detected by immunohistochemical staining methods. The results we obtained were as follows: 1. At day 1, fibers in epidermis, dermis and subcutaneous tissue in both groups B and Ba were not observed. However groups B and Ba exhibited fibers stained mildly and moderately, respectively, in muscle and connective tissues. At day 20 , the level of fiber in group B which was comparable to group C was less than that of in B group. 2. At day 3, fibronectin in group Ba was observed in the muscle. At days 15 and 20, fibronectin was increased in epidermis and dermis of group Ba compared with those of group B. 3. Type I collagen in subcutaneous tissue was observed at days 1, 3 and 7 in both groups B and Ba. However type I collagen was observed only in group Ba at day 15. In the epidermis of group Ba, type I collagen was observed at day 3 and maintained until day 20, while observing only at day 20 in group B. 4. For type IV collagen, both groups B and Ba showed similar results. 5. For laminin, both groups B and Ba showed similar results except the 7th day results. However after day 15, laminin was stained moderately and mildly in groups Ba and B, respectively. These results suggest that acupuncture may improve the burn wound healing by increasing fibronectin and type I collagen.