32P放射性同位素食管腔内照射对良性狭窄瘢痕形成的影响
Effects of 32P intracavitary irradiation on scar formation in benign esophageal strictures

摘要：目的 建立食管良性狭窄的模型，观察32P放射性同位素食管腔内照射对良性狭窄瘢痕形成的影响，为内镜下食管良性狭窄扩张后32P管腔内照射抑制瘢痕增生、预防再次狭窄提供实验依据。方法 18只健康成年家兔，通过外科手术行颈部食管环形切开后再吻合的方法建立食管良性狭窄模型，随机分成对照组、激素组及照射组，每组6只；术后第2天测量食管吻合口处内径，对照组给予生理盐水干预，激素组给予地塞米松干预，照射组给予32P放射性同位素干预，观察2周。观察指标包括：一般情况、体质量、干预结束后食管吻合口处内径，造模前及干预后检验肝功(ALT，AST)；处死家兔，取食管狭窄处组织观察大体病理并行HE染色，测定食管吻合口处组织羟脯氨酸含量。结果 成功建立食管良性狭窄的模型。2周后对照组食欲明显减退，激素组食欲稍差，照射组未出现食欲减退；照射组体质量比前2组都增加(P<0.05)；照射组食管吻合口处内径与前2组比较均明显增宽(P<0.05)；HE染色示照射组成纤维细胞数量明显减少，胶原纤维及肉芽组织均不显著；照射组羟脯氨酸含量比前2组都低(P<0.05)，接近正常食管的含量(P>0.05)；各组干预前后ALT及AST比较均无统计学差异(P>0.05)。结论 通过外科手术可成功建立家兔食管良性狭窄的模型；放射性同位素32P照射可以抑制食管狭窄处瘢痕形成，且优于激素治疗。
ABSTRACT: Objective To establish a benign esophageal stricture model and observe the effect of 32P radioactive isotopes on benign esophageal stricture scarring with intracavitary irradiation so as to provide experimental evidence for inhibiting scar hyperplasia and preventing esophageal restenosis after endoscopic dilation for benign esophageal stricture. Methods Benign esophageal stricture models were established in 18 healthy adult rabbits by annular incision and anastomosis. Then the rabbits were randomly divided into control group, hormone group and irradiation group, with six rabbits in each group. On day 2 after surgery, we measured inner diameter of the anastomotic stoma; then the control group received saline intervention, the hormone group was given dexamethasone, and the irradiation group was given 32P radioactive isotopes. The rabbits were observed for two weeks for their general condition and weight. After the intervention, we measured inner diameter of the anastomotic stoma. Liver functions (ALT and AST) were tested again before modeling and after intervention. Then the rabbits were put to death and had tissue in the esophageal stricture area removed for pathological examination and esophageal HE staining. We determined hydroxyproline (HYP) content of esophageal tissue around the anastomotic stoma. Results Benign esophageal stricture model was established successfully. After 2 weeks, the rabbits’ appetite was obviously diminished in control group and relatively poor in hormone group; obviously improved in irradiation group. The rabbits’ weight increased in radiation group compared with the other two groups (P<0.05). The esophageal inner diameter in irradiation group widened obviously compared with the other two groups (P<0.05). In irradiation group, the number of fibroblasts decreased obviously, collagen fiber and granulation tissue were not obvious; HYP content was lower than that in the other two groups, and was close to that in a normal