Effect of blocking angiotensin II type 1 receptor on wound healing in mouse skin full-thickness injury model

Abstract

Objective To observe the effect of angiotensin Ⅱ ( Ang Ⅱ ) type 1 receptor ( AT1R)on reepitheliazation,granulation tissue formation and growth factor production during wound healing,and explore the possible mechanism by which Ang Ⅱ influenced wound healing.Methods Two full-thickness skin wounds were created on the dorsum of C57/BL6J mice.Animals were treated with or without AT1R blocker,Losartan at a dose of 20 mg/kg daily after wounding.Specimens were taken from the wound of each mouse on the day 3,5,7,9,11,13 and 15 after wounding.Reepitheliazation and granulation tissue formation in wounded skin tissue were evaluated by hematoxylin and eosin (HE) staining.The production of growth factors in wounded tissue during the healing process was detected by using enzyme linked immunosorbent assay (ELISA).Results Treatment with AT1R blocker,Losartan,significantly inhibited the rate of reepithelialization and the thickness of granulation tissue as compared with untreated group at the day 5 and 7 after wounding.Moreover,peritoneal application of Losartan decreased the production of epidermal growth factor (EGF),vascular endothelial growth factor (VEGF) and basic fibroblast growth factor (bFGF) in the wounded tissues at the indicated time after wounding.Conclusion These results indicate that AT1R blocker impaired wound healing at least partially via inhibiting growth factors production. Key words: Angiotensin; Wound healing; Growth factors