兔肾下腹主动脉阻断对子宫缺血/再灌注损伤的影响

Effect of rabbit lower abdominal aortic occlusion on uterine ischemia/reperfusion injury

目的观察家兔肾下腹主动脉不同时间阻断后,血清细胞因子改变及子宫再灌注损伤情况,探讨腹主动脉阻断的安全性。方法将40只家兔随机分为4组,分别为肾下腹主动脉阻断20 min(B)、40 min(C)、60 min(D)组和假手术组(A),每组10只。假手术组不予阻断,其他3组均接受肾下腹主动脉阻断后再灌注处理。分别在术前(T 0)、再灌注10 min(T 1)、再灌注40 min(T 2)和再灌注90 min(T 3)抽取颈静脉血,酶联免疫吸附试验法(ELISA)检测血清中肿瘤坏死因子-α(TNF-α)、白介素-6(IL-6)浓度的变化;再灌注90 min后,将兔处死,取子宫组织,观察光镜下子宫肌层组织变化,采用免疫组织化学SP法和Western blot检测子宫肌肉组织中Toll样受体4(TLR4)和核因子-κB/p65(NF-κB/p65)的表达,并进行相关性分析。结果① C组在T 1时点IL-6浓度高于A组和B组,在T 2和T 3时间点TNF-α、IL-6浓度均高于A组和B组( P <0.05),D组在再灌注后各时间点血清TNF-α、IL-6浓度均高于其他3组( P <0.05);② A组子宫肌间组织结构正常,B组、C组、D组随着缺血时间延长,炎细胞浸润逐渐加重,间质肿胀明显;③子宫肌层组织中TLR4、NF-κB/p65蛋白表达在B、C、D 3组明显升高,且随着缺血时间的延长,呈上升趋势,尤其在C组和D组( P <0.05)。结论随着家兔肾下腹主动脉阻断时间的延长,再灌注损伤越严重,腹主动脉阻断20 min是较为安全时效,阻断40 min内损伤较小,相对安全。

Objective To observe the changes of serum cytokines and uterine reperfusion injury after blocking the infrarenal abdominal aorta in rabbits for different time, and to explore the safety of abdominal aortic occlusion. Methods 40 rabbits were randomly divided into 4 groups: lower extremity abdominal aorta blockade for 20 min(B), 40 min(C), 60 min(D) group and sham operation group(A), with 10 rats in each group. The sham operation group was not blocked, and the other 3 groups were treated with reperfusion after renal lower abdominal aorta occlusion. Ugular vein blood was taken before surgery(T 0), reperfusion for 10 min(T 1), reperfusion for 40 min(T 2), and reperfusion for 90 min(T 3). Enzyme-linked immunosorbent assay(ELISA) was used to detect changes in the concentration of tumor necrosis factor-α(TNF-α) and interleukin-6(IL-6) in serum. After 90 min of reperfusion, the rabbits were sacrificed and the uterus tissue was taken to observe the changes of myometrial tissue under light microscopy. The expression of Toll-like receptor 4(TLR4) and nuclear factor-κB/p65(NF-κB/p65) in uterine muscle tissue was detected by immunohistochemistry SP and Western blot, also with correlation analysis. Results ① The concentration of IL-6 in group C was higher than that in group A and group B at T 1 time point. The concentrations of TNF-α and IL-6 in group C were higher than those in group A and group B at the T 2 and T 3 time points( P <0.05). The serum levels of TNF-α and IL-6 were higher than those of the other three groups at each time point after reperfusion( P <0.05).② As the uterine myenteric tissue structure became normal in group A, group B, group C and group D. The blood time prolonged, the inflammatory cell infiltration gradually increased, and the interstitial swelling was obvious.③ The expression of TLR4 and NF-κB/p65 protein in the myometrium was significantly increased in the B, C, and D groups, and with the prolongation of ischemia time, an upward trend appeared, especially in group C and group D( P <0.05). Conclusion With the prolongation of the inferior abdominal aorta in rabbits, the reperfusion injury becomes more serious. Abdominal aorta occlusion for 20 min is a safe aging, 40 min blocking internal injury is relatively small and relatively safe.