Effect of ischemic-reperfusion injury induced by transient embolization for tumor tissue

本研究通过经导管血管造影术对兔VX2肿瘤局部注射可降解淀粉微球(DSM)，证实DSM闭塞了肿瘤血管。肿瘤内血流在DSM治疗后即刻迅速下降，并恢复到原来的水平。我们证明，DSM的抗肿瘤作用是通过将DSM注入肿瘤组织的动脉而获得的。丹参30 mg/kg单次给药组和每日给药3d组的肿瘤生长率与对照组相比有显著差异，肿瘤生长受到明显抑制。与对照组比较，丹参10 mg/kg/d连续给药3d可抑制肿瘤生长。本研究测定了注射DSM后肿瘤组织中超氧化物歧化酶(SOD)活性的时程变化。肿瘤组织血流再灌流后，超氧化物歧化酶活性明显降低。在肿瘤周围的肌肉中，观察到了与之相同的超氧化物歧化酶活性的时程变化。病理上，未见肿瘤血管被血栓阻塞。认为暂时性栓塞剂DSM的抗肿瘤作用仅次于缺血再灌注损伤现象。

In this study, rabbits with VX2 carcinoma received regional infusion of degradable starch microsphere(DSM) by transcatheter angiography, and it was confirmed that DSM occluded tumor vessels. Blood flow in the tumors decreased rapidly immediately after the DSM treatment and returned to the original level. We demonstrated that the antitumor effect was obtained by the infusion of DSM to the arteries by which the tumor tissues were fed. In the groups given the DSM for 30mg/kg by both single infusion and daily for 3 days, the tumor growth ratio was significantly different from the control group, tumor growth was significantly inhibited. The tumor growth ratio in the group given the DSM for 10mg/kg by daily for 3 days was inhibited to compare with the control group. In this study, the time course changes of the activity of superoxide dismutase(SOD) in the tumoral tissue were measured after injection of the DSM. The value of the activity of SOD was significantly decreased after re-perfusion of tumor tissue blood flow. In the muscles around the tumor, the same time course changes of the activity of SOD were observed.Pathologically, occlusion of the tumor vessels by thrombus was not observed. It was thought that the antitumor effect of the transient embolic agent DSM was secondary to the phenomenon of ischemic-reperfusion injury.