Gao Shang, Tang Kanglai, Zhang Jiqiang, Li Pao, Yang Zhijin, Cui Haifeng, Yang Mingyu, Tang Hong, Zhou Mei
Department of Orthopedics, Orthopedic Center of Chinese PLA, Southwest Hospital, Third Military Medical University, Chongqing, 400038, P.R.China.
Department of Orthopedics, Orthopedic Center of Chinese PLA, Southwest Hospital, Third Military Medical University, Chongqing, 400038,
Zhongguo Xiu Fu Chong Jian Wai Ke Za Zhi. 2017 May 15;31(5):574-581. doi: 10.7507/1002-1892.201611054.
To explore the effect of different intensity treadmill training on the repair of micro-injured Achilles tendon induced by collagenase in rats.
Seventy-two 8-week-old male Sprague Dawley rats (weighing, 200-250 g) were selected. After adaptive treadmill training for 1 week, rats were injected with 30 μL type I collagenase solution (10 mg/mL) into both Achilles tendons to make micro-injured Achilles tendon models. After 1 week of cage feeding, the rats were randomly divided into 3 groups: the control group, the low-intensity group, and the high-intensity group, 24 rats each group. The rats in control group could move freely, and the rats underwent daily treadmill training at the intensity of 13 m/min and 20 min/d in the low-intensity group and at the intensity of 17 m/min and 60 min/d in the high-intensity group. At immediate, 1 week, and 4 weeks after training, bilateral Achilles tendons were collected from 8 rats of each group for gross observation, histological analysis, and mechanical testing.
At immediate after training, there was no significant difference in the gross observation, histological observation, and biomechanical properties of the Achilles tendon between groups ( >0.05). The gross observation showed connective tissue hyperplasia near Achilles tendon and lackluster tendon in each group at 1 week; hyperplasia significantly reduced in the low-intensity group when compared with the control group, and there were more connective tissue and a large number of neovascularization in the high-intensity group at 4 weeks. At 1 week, there was no significant difference in the semi-quantitative histological total score between groups ( >0.05), but there were significant differences in vascularity between low-intensity group or high-intensity group and control group ( <0.05). At 4 weeks, the semi-quantitative histological total score was significantly higher in high-intensity group than control group and low-intensity group ( <0.05), and in control group than low-intensity group ( <0.05). There were significant differences in collagen arrangement, cell morphology, abnormal cells, and vascularity between low-intensity group and high-intensity group or control group ( <0.05). And there was significant difference in abnormal cells between high-intensity group and control group ( <0.05). The mechanical testing showed that there was no significant difference in cross-sectional area of the Achilles tendon, the ultimate force, tensile strength, and elastic modulus between groups at 1 week ( >0.05); the low-intensity group was significantly higher than the control group in the ultimate force and the tensile strength ( <0.05), and than high-intensity group in the ultimate force and elastic modulus ( <0.05), but no significant difference was found in the other indexes between groups ( >0.05) at 4 weeks.
Low-intensity treadmill training can promote the repair of rat micro-injured Achilles tendon induced by collagenase.
探讨不同强度跑步机训练对胶原酶诱导的大鼠微小损伤跟腱修复的影响。
选取72只8周龄雄性Sprague Dawley大鼠（体重200 - 250 g）。适应性跑步机训练1周后，向大鼠双侧跟腱注射30 μLⅠ型胶原酶溶液（10 mg/mL），制备微小损伤跟腱模型。笼养1周后，将大鼠随机分为3组：对照组、低强度组和高强度组，每组24只。对照组大鼠自由活动，低强度组大鼠每天以13 m/min的速度、20 min/d进行跑步机训练，高强度组大鼠每天以17 m/min的速度、60 min/d进行跑步机训练。训练后即刻、1周和4周，每组取8只大鼠双侧跟腱进行大体观察、组织学分析和力学测试。
训练后即刻，各组跟腱的大体观察、组织学观察及生物力学性能无显著差异（P>0.05）。1周时大体观察显示各组跟腱附近结缔组织增生，肌腱色泽暗淡；与对照组相比，低强度组增生明显减轻，4周时高强度组结缔组织更多且有大量新生血管形成。1周时，各组半定量组织学总分无显著差异（P>0.05），但低强度组或高强度组与对照组之间血管分布有显著差异（P<0.05）。4周时，高强度组半定量组织学总分显著高于对照组和低强度组（P<0.05），对照组高于低强度组（P<0.05）。低强度组与高强度组或对照组之间在胶原排列、细胞形态、异常细胞及血管分布方面有显著差异（P<0.05）。高强度组与对照组之间异常细胞有显著差异（P<0.05）。力学测试显示，1周时各组跟腱横截面积、极限力、拉伸强度及弹性模量无显著差异（P>0.05）；4周时，低强度组极限力和拉伸强度显著高于对照组（P<0.05），极限力和弹性模量高于高强度组（P<0.05），但其他指标组间无显著差异（P>0.05）。
低强度跑步机训练可促进胶原酶诱导的大鼠微小损伤跟腱的修复。
