| Objective:To observe the inhibition effect of applying sodium tanshinon II A sulfonate(STS) local injections to hypertrophic scar after wound healing of rabbit ears.Methods:Ten New Zealand rabbits were randomly selected and adaptive raised. After 48 hours, scar model of rabbit ears is established under general anesthesia. In the ventral sides of rabbit ears, square wounds are made and the length of each side is 2 centimeter. There are three wounds in each left ear and three wounds in each right ear. So there are sixty wounds in total in which forty wound is studied. Experimental wounds were divided into two groups: Experimental group includes group A, B and C; control group is group D. Group A includes ten scars. After each wound is epithelial(the 28th days after injury), STS is applied to each scar of group A by the way of local injection once a week, which was completed by three times in total, each dosage of STS is 0.05mg/scar. Group B includes ten scars. each dosage of STS is 0.1mg/scar. It is same with group A in respects of time, frequency, cycle and dosage. Group C include ten scars. each dosage of STS is 0.2mg/scar. It is same with group A in respects of time, frequency, cycle and dosage. Group D which includes ten scars is control group. Normal saline is applied in each scar and each dosage is 0.04ml/scar. It is same with group A in respects of time, frequency and cycle. Before local injections (the 28th days after injury) and three weeks after local injections (the 47th days after injury),we should record and measure size, thickness, color and hardness of the scars of the rabbit ears. After local injections of three weeks at each scar of groups,40 scars are cutted under general anesthesia and performed with hematoxylin-eosin stain, Masson's trichrome stain, pathology observation and electron microscopy analysis.Results:Compared with the control group, scar tissue hyperplasia of experimental group is lighter, color is lighter,texture is softer and thickness reducing range (x±s) is wider. Thickness reducing ranges of group A, B and C are 1.427±0.067mm,1.504±0.074mm and 1.662±0.090mm, respectively; But thickness reducing ranges of group D is 0.664±0.098mm. Thickness reducing ranges of group A, B and C is wider than thickness reducing ranges of group D. Their difference was statistically significant (p<0.05); Contrasted thickness reducing ranges of group A with thickness reducing ranges of group C, the difference was statistically significant (p<0.05). Compared experimental group with the control group in the microscope, collagen fibers in scars are looser and more regular; Lymphocytes, plasma cells, and neutrophils in scars are decreasing, which scatter or infiltrate around the blood vessels; Number of blood vessels lessen. The count of inflammatory cells (x±s) of group A, B, C and D are 20.92±2.90,16.66±2.38.8.98±2.09,47.64±8.27, respectively. By statistical processing, compared experimental group with the control group, their difference was statistically significant (p<0.05); compared groupA, B and C, their difference was statistically significant (p<0.05).The area of collagen fibers (x±s) of group A, B, C and D are 73.70±2.29%,65.92±2.24%,56.38±2.75%,85.90+2.81%, respectively. By statistical processing, compared experimental group with the control group, their difference was statistically significant (p<0.05); compared groupA, B and C, their difference was statistically significant (p<0.05). Compared experimental group with the control group detecting by the electronic microscope, collagen fibers in scars are looser and more regular. And the number of fibroblast is manifestly reducing its volume become small and rough endoplasmic reticulum is less development in meanwhile distend partly. The nucleus of fibroblast are filled with heterochromatin. A phenomenon of fibroblastic autolysis is observed.Conclusion:It is obvious inhibitory effect of applying STS local injections to hypertrophic scar of rabbit ears.
|
PDF Full Text Request