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目的:建立一种简便可控、质量可靠的肢体挤压缺血-再灌注损伤大鼠模型,并评估其有效性及稳定性。方法:通过定压、恒容标准技术建立动物模型,即采用自锁式尼龙扎带行大鼠右侧后肢近端加压捆扎阻断后肢血流,尼龙扎带宽度为5 mm,通过压力监测装置维持阻断压力在(300±20)mmHg。大鼠趾掌表现为苍白青紫、发凉,并经激光多普勒血流成像仪验证肢体血流被成功阻断,即造模成功。给予大鼠单侧后肢血流阻断4 h,然后于不同再灌注时间(0.5、2、4、8 h)后收集缺血肢体腓肠肌、肾脏、肝脏、肺组织及血清标本(n n=6/组)。Masson染色观察腓肠肌组织学变化,HE染色观察肾脏、肝脏及肺组织学改变,同时检测各组大鼠血清谷丙转氨酶(ALT)、谷草转氨酶(AST)、尿素氮(BUN)、肌酐(Cr)、肌酸激酶(CK)、丙二醛(MDA)水平并进行组间比较。n 结果:与对照组比较,肢体缺血4 h后大鼠腓肠肌出现明显肿胀及淤血表现,Masson染色镜下可见腓肠肌纤维肿胀、排列不规则、肌纤维间隙增宽;于再灌注后不同时间点(0.5、2、4、8 h)观察,腓肠肌损伤逐渐加重,局部肌细胞出现坏死,再灌注各组腓肠肌湿重与对照组的差异均有统计学意义(n P<0.05)。对照组血清CK水平为(38.78±2.59)U/L,肢体缺血(4 h)组(621.97±98.77)U/L,肢体缺血-再灌注(0.5、2、4、8 h)组血清CK水平分别为(9 400.25±1 051.30)U/L,(6 312.27±3 056.83)U/L,(3 511.03±871.83)U/L和(5 509.55±675.13)U/L,差异有统计学意义(n F=39.35,n P<0.05),肢体缺血-再灌注(0.5 h)组血清CK水平最高。在肢体缺血-再灌注后大鼠肾脏、肝脏和肺组织均出现不同程度的病理和功能改变。肾脏出现肾小球大小不一,肾小管上皮细胞水肿,管腔狭窄,肾小球萎缩等变化。对照组血清BUN水平为(57.1±2.2)mg/L,肢体缺血(4 h)组(183.9±28.3)mg/L,肢体缺血-再灌注(0.5、2、4、8 h)组血清BUN水平分别为(400.6±22.8)mg/L,(396.9±20.5)mg/L,(371.8±64.4)mg/L和(644.5±108.7)mg/L,差异有统计学意义(n F=83.42,n P<0.05),肢体缺血-再灌注(8 h)组血清BUN水平最高。肝脏出现肝细胞水肿,汇管区小叶间动脉充血,肝血窦扩张、红细胞渗出,气球样变及小叶中央出血等改变。对照组血清ALT水平为(54.71±6.01)U/L,肢体缺血(4 h)组为(113.62±21.86)U/L,肢体缺血-再灌注(0.5、2、4、8 h)组血清ALT水平分别为(168.92±14.56)U/L,(458.36±89.27)U/L,(436.39±55.85)U/L和(703.01±43.57)U/L,差异有统计学意义(n F=165.5,n P<0.05),肢体缺血-再灌注(8h)组血清ALT水平最高。肺组织出现肺泡壁断裂,肺泡腔及间质内充血,气道闭塞,淋巴细胞浸润等表现。n 结论:通过稳定压力和恒定受压肌肉容积建立的大鼠模型模拟了肢体急性挤压缺血-再灌注损伤的疾病状态,稳定性强,可重复性高,可用于肢体挤压缺血-再灌注损伤相关的后续基础研究。“,”Objective:To establish a simple, controllable and reliable rat model of limb crush ischemia-reperfusion injury. The validity and stability of the model were verified.Methods:The animal models were established by a technique that provides constant pressure and standard muscle volume damaged by compression. The blood flow of the right hind limb was blocked by self-locking nylon band and a pressure monitoring device was used to monitor the pressure of the device. The width of nylon band was 5 mm and the pressure was maintained at 300±20 mmHg. Occlusion of blood flow of lower limb was confirmed by observing the changes of extremities and laser Doppler flow imaging. The blood flow was blocked for 4 h, then the gastrocnemius muscle of the ischemic-reperfusion limb, kidney, liver, lung and blood samples (n n=6/group) were collected in different reperfusion groups (0.5, 2, 4, 8 h). Masson staining was used to detect the pathological changes of gastrocnemius muscle. Histological changes of kidney, liver and lung in different groups were observed by HE staining. The changes of biochemical indexes such as plasma ALT, AST, BUN, Cr, CK and MDA in different groups were detected and compared between groups, respectively.n Results:Swelling and hyperemia was found in the ischemic limb gastrocnemius muscles 4 hours after blood flow occlusion compared with the control group. Masson staining results showed that the muscle fibers of ischemic limbs were swollen, irregularly arranged, and the gap between muscle fibers was widened. At different time points after ischemia-reperfusion (0.5, 2, 4, 8 h), the muscle injury was further aggravated, histological characteristics of necrosis were observed in local muscle cells.The differences of gastrocnemius muscle wet weight between reperfusion groups and the control group were statistically significant (n P<0.05). The serum CK level of the control group was 38.78±2.59 U/L, the limb ischemia-reperfusion (4 h) group 621.97±98.77 U/L, and the serum CK levels in limb ischemia-reperfusion (0.5, 2, 4, 8 h) groups were 9 400.25±1 051.30 U/L, 6 312.27±3 056.83 U/L, 3 511.03±871.83 U/L and 5 509.55±675.13 U/L, respectively (n F=39.35, n P<0.05). The serum CK level in limb ischemia-reperfusion (0.5 h) group was the highest.After limb ischemia-reperfusion, the kidney, liver and lung tissue showed different degrees of pathological and functional changes. Renal injury was characterized by different glomerular sizes, edema of renal tubular epithelial cells, narrowing of lumen and atrophy of glomeruli. The serum BUN level of the control group was 57.1±2.2 mg/L, the limb ischemia-reperfusion (4 h) group 183.9± 28.3 mg/L, and the serum BUN levels in limb ischemia-reperfusion (0.5, 2, 4, 8 h) groups were 400.6±22.8 mg/L, 396.9±20.5 mg/L, 371.8± 64.4 mg/L and 644.5±108.7 mg/L, respectively (n F=83.42, n P<0.05). The serum BUN level was the highest in limb ischemia-reperfusion (8 h) group. The liver lesions showed edema of hepatocytes, congestion of interlobular artery in portal area, dilatation of hepatic sinuses, exudation of red blood cells, balloon like change and central lobular hemorrhage. The serum ALT level of the control group was 54.71±6.01 U/L, the limb ischemia-reperfusion (4 h) group 113.62±21.86 U/L, and the serum ALT levels in limb ischemia-reperfusion (0.5, 2, 4, 8 h) groups were 168.92±14.56 U/L, 458.36±89.27 U/L, 436.39±55.85 U/L and 703.01±43.57 U/L, respectively (n F=165.5, n P<0.05). The serum ALT level was the highest in limb ischemia-reperfusion (8 h) group. Pulmonary tissue showed alveolar wall rupture, alveolar cavity and interstitial congestion, airway occlusion and lymphocyte infiltration.n Conclusion:A rat model established with stable pressure and constant compressed muscle volume simulates the disease of limb acute crush ischemia and reperfusion injury in this study. The model is very stable, reliable and highly reproducible, which can be used in further research of limb crush ischemia-reperfusion injury.