COMPARISON OF THE EFFICACY OF LOSARTAN, HYDROCORTISONE AND ACETYLSALICYLIC ACID (ASA) IN PREVENTING THE DEVELOPMENT OF FIBROUS SCAR TISSUE IN SKELETAL MUSCLE

ABSTRACT Objective: To analyze fibrous scar tissue inhibition capacity with the use of losartan, hydrocortisone and acetylsalicylic acid. Method: The sample consisted of 120 male heterogeneic Wistar rats with a muscle laceration model. The rats were divided into four groups of 30 animals each: control group, losartan group, ASA group and hydrocortisone group. The animals were anesthetized and a 2.5 cm longitudinal incision was made in the left thoracolumbar paravertebral region. The muscles were subjected to a Grade III lesion caused by applying Kelly hemostatic forceps for 60 seconds, followed by sectioning with scissors. The skin was sutured with 3-0 nylon monofilament thread. The animals were placed in individual cages with plenty of food and water. The losartan group received losartan diluted in water at a dose of 0.1 mg/mL (10 mg/kg/day), the ASA Group received a 3 mg/mL ASA solution (300 mg/kg/day), and the hydrocortisone group received a 0.2 mg/mL hydrocortisone solution (20 mg/kg/day). Results: The control, losartan, hydrocortisone and aspirin groups had a fibrotic area of 0.95 ± 0.35 mm, 0.55 ± 0.34 mm, 0.93 ± 0.33 mm, and 0.66 ± 0.36 mm, respectively. We observed a significantly smaller fibrotic area in the losartan group compared to the control (p=0.01) and hydrocortisone (p=0.01) groups. There were no significant differences among the other groups. Conclusion: The healing of striated skeletal muscle produced less fibrous scar tissue when exposed to losartan in comparison to the control group or the hydrocortisone group. Level of Evidence I; Randomized double-blind placebo-controlled study.摘要 目的：分析氯沙坦（losartan）、氢化可的松（hydrocortisone）与乙酰水杨酸（acetylsalicylic acid，ASA）对纤维瘢痕组织的抑制作用。 方法：本研究纳入120只雄性远交系Wistar大鼠，建立肌肉裂伤模型。将大鼠分为4组，每组30只：对照组、氯沙坦组、ASA组、氢化可的松组。对大鼠实施麻醉后，于左侧胸腰椎旁椎旁区域做2.5 cm纵行切口；使用凯利止血钳夹持60秒造成Ⅲ级肌肉损伤，随后用剪刀剪断肌肉；以3-0尼龙单丝线缝合皮肤。将大鼠单笼饲养，提供充足的食物与饮水。氯沙坦组给予溶于饮用水的氯沙坦溶液，剂量为0.1 mg/mL（10 mg/kg/天）；ASA组给予3 mg/mL的乙酰水杨酸溶液（300 mg/kg/天）；氢化可的松组给予0.2 mg/mL的氢化可的松溶液（20 mg/kg/天）。 结果：对照组、氯沙坦组、氢化可的松组与ASA组的纤维化面积分别为0.95±0.35 mm、0.55±0.34 mm、0.93±0.33 mm与0.66±0.36 mm。相较于对照组（p=0.01）与氢化可的松组（p=0.01），氯沙坦组的纤维化面积显著更小；其余组间无统计学差异。 结论：与对照组或氢化可的松组相比，经氯沙坦处理的横纹肌愈合后产生的纤维瘢痕组织更少。证据等级：I级；随机双盲安慰剂对照研究。