pUDKH基因治疗犬下肢缺血后对血管、肌肉组织的影响

Effects of pUDKH administration locally on arteries and muscles in dogs with hindlimb ischemia

目的：观察pUDKH（携带肝细胞生长因子基因的质粒）基因治疗犬下肢缺血后对其血管和肌肉组织病理学的影响．方法：杂种犬在静脉内注射苯巴比妥钠麻醉下，于左后侧腹股沟在股动脉由髂外动脉分支处的起始端进行全结扎，造成肢体缺血模型．模型犬被随机分为对照组和pUDKH处理组，并在结扎后即刻分别注射pUDK（空白质粒）或pUD—KH．于手术后3mo，行左髂外动脉造影术，测定股动脉血流量和下肢远端局部温度，并从被结扎的后肢股动脉及内外侧肌肉取组织标本，经常规组织病理切片染色，光学显微镜下观察．结果：3mo时血管造影pUDKH组可见明显血管网的形成，而转移空质粒的对照组仅见少量新生血管；此时转移pUDKH组犬股动脉血流量已恢复到结扎前的水平，而对照组股动脉血流量仅为结扎前的1／5～1／3；转移pUDKH组结扎侧肌肉温度与健侧相比无明显差异，而对照组两肢体肌肉温度却相差1～2℃．组织学观察对照犬可见结扎点远端股动脉塌陷，肌束间动脉管壁变厚，管腔变小甚至消失，少见新生的小血管；pUDKH处理组犬结扎点远端股动脉管腔开放，肌束间小动脉壁均普遍未见增厚，管腔亦未缩小；对照犬结扎侧肌纤维变性、断裂、肌束内水肿、脂肪性变，pUDKH处理组结扎侧的肌肉组织中上述病变不明显．结论：pUDKH的局部注射对犬下肢缺血后血管和肌肉具有保护作用．

AIM： To observe the effects of pUDKH administration locally on blood vessels and muscles in dogs with hindlimb ischemia. METHODS： Dogs were anesthetized with an intravenous injection of sodium pentobarbital （30 mg/kg）. Then the left external iliac artery as well as all of the above arteries were ligated completely with silk thread. Thus the completely ischemic hindlimb model was established. The dogs with completely ischemic hindlimb were randomly divided into 2 groups： control group （control vector pUDK） and HGF- transferred group （pUDKH） , 4 -6 dogs each. Then pUDKH or pUDK was injected directly into the left ischemic limb muscles. Three months （90 d） after injection, left external iliac arteriography was performed, blood flow rate of the left femoral artery was quantified and the temperature of distal muscle in hindlimb was measured. At the same time, the left femoral artery and femoral around muscles at the sites of injection of pUDKH and pUDK plasmids were removed and stained with HE to observe their histopathological changes by light microscopic examination. RESULTS： The degree of augmentation of collateral vessel formation was significantly greater than that treated by control vector in hindlimb ischemia models. In addition, the blood flow rate of femoral artery in dogs treated with pUDKH was recovered on day 90, while the flow rate was only 1/5 to 1/3 in control dogs. Degeneration and breakage of muscle fibers and edema among muscle bundles were observed in ischemic limb of control dogs, but in ischemic hindlimb transfected with pUDKH, no significant pathological changes were found. For control dogs, collapse of the left femoral artery, thickening of vessel wall and stenosis even occlusion of small blood vessel among muscle bundles were observed, few new blood vessels were found. But in pUDKH dogs, above all were almost normal. CONCLUSION： pUDKH has a protective effect on blood vessels and muscles in dogs with hindlimb ischemia.