大鼠糖尿病足胫骨横向骨搬移模型的建立

Establishment of a rat model of transverse tibial bone transfer on the diabetic foot

目的建立一种大鼠糖尿病足胫骨横向骨搬移模型。方法将40只高脂饲养5周后的SD大鼠腹腔注射链佐脲菌素制作糖尿病模型,并以随机血糖≥16.7 mmol/L为造模成功标准。实验期间在适应性饲养结束后每周监测一次体重、进食量、饮水量、排便量以及血糖的变化,直到连续3周随机血糖≥16.7 mmol/L。待血糖稳定后运用随机数字表法将存活的34只糖尿病大鼠分为两组,实验组:安装横向骨搬移外固定支架,切除大鼠足背皮肤,并进行横向骨搬移;对照组:安装横向骨搬移外固定支架并切除大鼠足背皮肤,但不进行横向骨搬移。在安装外固定支架后第1、5、10、15、20天记录创面变化。在横向骨搬移周期完成后(即胫骨横向骨搬移造模术后24 d),两组分别随机抽取1只大鼠进行血管造影,其余大鼠处死后观察下肢皮肤变化,并比较两组大鼠下肢皮肤组织CD31免疫组化染色的光密度值(AOD)。结果随机血糖由造模前(6.89±1.03)mmol/L升高到末次检测的(25.91±6.42)mmol/L,并且连续3周血糖均≥16.7 mmol/L。实验组足背创面在第5、10、20天时溃疡愈合百分比均显著高于对照组,差异均有统计学意义(P<0.05)。大体观察与血管造影都发现实验组横向骨搬移侧下肢有更丰富的血管。CD31免疫组化染色发现实验组的AOD为0.60±0.23,显著高于对照组的0.37±0.13,差异有统计学意义(t=3.722,P=0.001)。结论在成功制作的糖尿病大鼠模型基础上,通过自主设计的横向骨搬移外固定支架建立了下肢微循环改善的胫骨横向骨搬移模型。

Objective To establish a rat model of transverse tibial bone transfer on the diabetic foot.Methods A diabetic model was created by intraperitoneal injection of streptozotocin into 40 SD rats after 5 weeks of high-fat feeding,taking random blood glucose≥16.7 mmol/L as the criterion for successful modeling.Changes in body weight,food intake,water intake,faecal output and blood glucose were monitored every week after the acclimatization period until random blood glucose≥16.7 mmol/L was observed for 3 running weeks.After the blood glucose was stabilized,34 surviving diabetic rats were divided into 2 groups using a random number table.In the experimental group,a transverse transfer outer frame was installed and transverse tibial bone transfer performed after removal of the skin over the dorsal foot;in the control group,a transverse transfer outer frame was installed and the skin over the dorsal foot removed but no transverse tibial bone transfer performed.The wound changes were recorded on the 1,5,10,15 and 20 days after installation of the transverse transfer outer frame.After completion of transverse tibial bone transfer(24 days after modeling of transverse tibial bone transfer),one rat was randomly chosen from each of the 2 groups for angiography while the rest rats were sacrificed for observation of the skin changes on the lower limbs.The densitometric values of CD31 immunohistochemical staining were compared between the 2 groups.Results The random blood glucose increased from(6.89±1.03)mmol/L before modeling to(25.91±6.42)mmol/L at the last test,keeping at≥16.7 mmol/L for 3 running weeks.The percentages of ulcer healing of the foot dorsal wound in the experimental group on days 5,10,and 20 were significantly higher than those in the control group(P<0.05).Gross observation and angiography found more abundant vessels in the lower extremity on the side of transverse transfer in the experimental group.The immunohistochemical staining of the lower limb skin tissue for CD31 found an AOD value of 0.60±0.23 in the experimental group,significantly higher than that in the control group(0.37±0.13)(t=3.722,P=0.001).Conclusion A rat model of transverse tibial bone transfer has been successfully established through installation of a self-designed transverse transfer outer frame on the basis of a successful rat model of diabetic foot,characterized by improved microcirculation in the lower limbs.