不同温度下阻断胎羊肺动脉对胎羊中枢系统的影响

Effect of blocking fetal sheep pulmonary artery at different temperatures on fetal sheep central nervous system

目的观察不同温度下阻断胎羊肺动脉对胎羊中枢神经系统的影响,探讨低温对大脑的保护作用。方法2017年1月至2019年12月,将18只孕羊(孕120~140 d),南方山羊种,由广州市白云区隆归兴科动物养殖场提供,采用完全随机分组分为常温组(n=6)、低温组(n=6)和对照组(n=6)。分别在不同时间点采集胎羊的上腔静脉血,检测白细胞介素(IL)-1、超氧化物歧化酶(SOD)、神经元特异性烯醇化酶(NSE)和S100B蛋白。取左侧顶叶脑组织,做大体病理和电镜检测。取胎羊大脑,计算组织含水率用以表示不同实验组大脑水肿的程度。结果实验过程中3组胎羊NSE随时间明显上升(F=14.531,P<0.01),3组间差异有统计学意义(F=4.691,P<0.05);S100B差异有统计学意义(F=3.787,P<0.05)。3组胎羊血中IL-1β低温组与对照组之间的差异无统计学意义(F=4.017,P>0.05)。胎羊血中SOD组之间差异无统计学意义(F=0.869,P>0.05)。3组大脑含水率差异有统计学意义(F=11.410,P<0.01)。大体病理在低温组和常温组动物脑组织都是轻微损害,低温组脑组织的损害更轻。结论胎羊阻断肺动脉模型对胎羊的大脑有较明显的影响,宫内羊水转流降温到亚低温可减轻胎羊心脏操作对大脑的损害。

Objective To observe the effect of blocking fetal sheep’s pulmonary artery at different temperatures on the central nervous system in fetal sheep.Methods Eighteen pregnant goats were randomly divided into normal temperature group(n=6),low temperature group(n=6),control group(n=6).The vena cava blood was collected at different time points to detect interleukin-1(IL-1),superoxide dismutase(SOD),neuron specific enolase(NSE)and S100B protein.Brain tissues were subjected to the examinations for gross pathology and electron microscopy.The fetal sheep brain tissue water content was calculated.Results Umbilical artery PI values changed with time(F=3.491,P<0.05);NSE increased significantly with time(F=14.531,P<0.01),and the difference among the three groups was significant(F=4.691,P<0.05);the difference in S100B was obvious(F=3.787,P<0.05).There was no significant difference in IL-1βbetween hypothermia group and control group(P>0.05).There was no statistically significant difference in SOD among the three groups(F=0.869,P>0.05).Brain water contents among the three groups were statistically significant(F=11.410,P<0.01).The brain tissue in the hypothermia group was less damaged.Conclusion Blocking pulmonary artery has a significant effect on the brain of fetal sheep.Intrauterine amniotic fluid diversion to mild hypothermia can reduce the damage to the brain in heart operation of fetal sheep.