The Effect of Simultaneous Steroid and Verapamil Injection on Scar Formation in the Incisional Wound of Rat

Kim, Yong Oook; Kim, Sung Min; Jo, Nam Hoon; Nam, Taik Sang

Abstract

The wound healing in adult mammals is a complex process that inevitably leaves scar. Various treatment modalities have been investigated to minimize the scar formation, and a few of them succeeded. Intra-lesional injection of steroids is one of the methods that have been widely accepted for the treatment of specific scars such as keloids or hypertrophic scars. On the other hand, there have been some attempts made to reduce the scar by enhancing the expression of matrix metalloproteinase(MMPs) because it results in degradation of collagens in scar tissues. Verapamil, a calcium channel blocker, was one of the few factors promoting the expression of MMPs such as collagenases by altering the shape of fibroblasts from a bipolar spindle type to a round one. No investigation, however, has been done to elucidate the effect of simultaneous intra- lesional injection of steroid and verapamil to wounds on early scar formation. To investigate the effect of scar reduction by injecting steroid and verapamil simultaneously, we examined morphologic finding of tissue and we measured width of scar followed by incision wounds treated with normal saline(Control group), steroid(Group A), verapamil(Group B) and both steroid and verapamil (Group C), respectively. The scar width significantly reduced in Group B and Group C 2 and 4 weeks after the incision and in Group A 8 weeks after incision, in comparison with control group. At that time the scar width in Group C significant reduced compared to those of other groups. Furthermore the collagen fibers were less, thicker and more regularly arranged in the scar tissue in group C 8 weeks after incision than those in the other groups and their structure was most close to the normal one of the dermis. The contour of fibroblasts in Group B and Group C looked rounder than that in Group A and control group. In conclusion, simultaneous intra-lesional injection of steroid and verapamil decreases collagen deposition into the wound and subsequently minimize scar width.