【作者】 王勇；

【导师】 任伯绪；

【作者基本信息】 长江大学 ， 外科学， 2013， 硕士

【摘要】 目的：通过建立兔脑局灶性脑缺血模型,运用CT灌注成像(CT perfusion imaging, CTPI)测量缺血区的脑血流量(cerebral blood flow, CBF)、脑血容量(cerebral blood volume, CBV)、平均通过时间(mean transit time, MTT)参数的差异性,结合行为神经学评分、TTC染色和光镜下形态学改变,从而探讨在CT灌注下莲心碱对改善兔脑缺血再灌注损伤的保护作用。材料和方法：30只SD大白兔随机分为三组,分别为空白对照组、缺血损伤组和莲心碱保护组,每组各10只,利用线栓法达到脑缺血再灌注兔脑模型(栓塞6h,再灌注18h后各进行神经行为学评分),空白对照组无须手术。缺血损伤组模型栓塞6h行第一次CT灌注扫描,拔出鱼线恢复灌注后给予等容量生理盐水,18h(即MCAO24h)后再行一次CT灌注扫描,记录以上扫描数据CBV、CBF和MTT值；莲心碱保护组栓塞6h同样也行首次CT灌注扫描,拔出鱼线恢复灌注后给予莲心碱(3mg/kg体重),18h(即MCAO24h)后再行一次CT灌注扫描,记录以上扫描数据CBV、CBF和MTT值。结束后取脑进行病理学检查和TTC染色,观察光镜下组织形态学改变,并计算缺血损伤组和莲心碱保护组TTC染色梗死面积及CTPI各参数图所示缺血区体积占脑组织百分比大小。结果经线栓法建立的兔脑缺血模型,缺血损伤组成功5只(50%,5/10),莲心碱保护组成功3只(30%,3/10)。CT灌注下缺血损伤组和莲心碱保护组间的CBF、CBV、MTT参数也具有显著变化。参考正常兔脑左侧CT灌注参数CBF、CBV、MTT值,梗死区中CBF值急速降低,CBV值有所下降,MTT值则显著延长。在梗死区中对以上数据进行单因素方差分析显示缺血损伤组6h与空白对照组的CBF、CBV、MTT (P<0.05)有统计学意义；莲心碱保护组6h与空白对照组的CBF、CBV、MTT (P<0.05)有统计学意义；莲心碱保护组6h与缺血损伤组6h的CBF、CBV、MTT(P>0.05)无统计学意义；缺血损伤组6h与缺血损伤组24h的CBF、CBV、MTT (P>0.05)无统计学意义；莲心碱保护组6h与莲心碱保护组24h的CBF、CBV、MTT (P>0.05)无统计学意义；莲心碱保护组24h与缺血损伤组24h的CBF、CBV、 MTT(P>0.05)无统计学意义。在缺血半暗带(ischemic penumbra, IP)区中对以上数据进行单因素方差分析显示IP区中缺血损伤组6h与空白对照组的CBF、MTT (P<0.05)有统计学意义,CBV组间(P>0.05)无统计学意义；莲心碱保护组6h与空白对照组的CBF、MTT (P<0.05)有统计学意义,CBV组间(P>0.05)无统计学意义；莲心碱保护组6h与缺血损伤组6h的CBF、CBV、MTT(P>0.05)无统计学意义；缺血损伤组6h与缺血损伤组24h的CBF、CBV (P<0.05)有统计学意义,MTT组间(P>0.05)无统计学意义；莲心碱保护组6h与莲心碱保护组24h的CBF(P<0.05)有统计学意义,CBV、 MTT组间(P>0.05)无统计学意义；缺血损伤组24h与莲心碱保护组24h的CBF、CBV(P<0.05)有统计学意义,MTT组间(P>0.05)无统计学意义；莲心碱保护组24h与空白对照组的CBF、 CBV、 MTT (P>0.05)无统计学意义。最后将缺血损伤组和莲心碱保护组24h的CTPI各参数图及TTC染色所示缺血区体积占脑组织百分比比较,结果显示TTC有统计学意义(P<0.05)；CBF有统计学意义(P<0.05)；CBV有统计学意义(P<0.05)：MTT有统计学意义(P<0.05)。莲心碱保护组的脑梗死面积较缺血损伤组显著缩小,同时CBF、CBV、MTT参数伪彩图缺血区与TTC染色的梗死面积均呈正比例增大,以CBV相关性最高。结论：经MCAO建立的兔脑缺血再灌注损伤模型稳定可靠,可应用于临床影像设备检查和研究；CT灌注成像能够精准的显示脑组织梗死病灶的部位和面积,并可预测和评价其动态的演变过程；缺血损伤组(24h)较缺血损伤组(6h)CBV和CBF进一步降低,MTT延长,符合脑缺血再灌注损伤的原理；莲心碱保护组(24h)较缺血损伤组(24h)IP区CBV、CBF增加,梗死面积减少；由此可以证明中草药莲心碱对兔脑模型缺血再灌注损伤有显著保护作用。更多还原

【Abstract】 Objective:Having established the model of brain cerebral focal ischemia of rabbits, using the parametric difference of CBF, CBVand MTT of cerebral ischemia area by CT perfusion and combining neurobehavioral score, TTC stained and morphological changes under the optical microscope, we discussed the protection of the liensinine treated the rabbits with brain ischemia-reperfusion injury by the CT perfusion.Materials and methods:30New Zealand white rabbits were randomly divided into three groups:the control group,ischemic injury group and liensinine protection groups, each of them had10rabbits, using of suture occluded method to establish the mode of reperfusion of rabbits with cerebral ischemia(observed twice neurologic deficit score in rabbits after blocking the artery for6hours and reperfusing18hours), the control group had no surgery. Ischemia injury group model performed the CT perfusion scanning for the first time after obstructing the cerebral artery for6hours. After Pulling out the line to recover reperfusion we gave the physiological saline the same capacity as the plasma, and scaning it again under the CT when had reperfused forl8h(equality of MCAO24h), recorded above scanning data:CBV,CBF and MTT value. The rabbits with their cerebral artery being obstructed in liensinine protection group received also did CT perfusion scanning, pull out the line recovery the infusion with liensinine (3mg/kg), and after18hours (equality of MCAO24h) followed CT perfusion scanning again. We similarly recorded above scanning datas:CBV, CBF and MTT value. After the last scaning the above groups had to be tested neurologic deficit score, and then we took the cerebral tissues to have a pathological examination and TTC staining. We observed the morphological changes of tissues ischemia of the rabbits which being processed, calculated TTC staining area which had been infarcted and the volume percentage of ischemic area of brain tissue that showed by CTPI parameters graphs.Results:To establish model of rabbit with cerebral ischemia injury, but successed only5rabbits(50%,5/10)by the way of MCAO, liensinine protection group successed only3rabbits(30%,3/10). After MCAO surgery changed the rabbit model of cerebral ischemia cerebral blood microcirculation. The parameters of the CBF, CBV and MTT under the CT perfusion had also significant change during the ischemic injury group and the liensinine protection group.Referred the value of the CT perfusion parameters such as CBF, CBV and MTT on the left side of the brain in the normal rabbit. The CBF value of the infarction area rapidly decreased, the CBV value also decreased, but MTT value increased obviously. When established the medols for6hours the above datas had been performed the One-way ANOVA, which showed that the comparision of the CBF,CBV and MTT values between the ischemic injury group and the blank control group (P<0.05) had statistical significance,the CBF,CBV and MTT values (P<0.05) had statistical significance between liensinine protection group and the control group, But the comparision of CBF,CBV and MTT values (P>0.05) no statistical significance between liensinine protection group and ischemic injury group among groups; the comparison of CBF,CBV and MTT values had(P>0.05) no statistical significance between the Ischemia injury group(6h) and the ischemic injury group (24h); the comparison of CBF,CBV and MTT values had(P>0.05) no statistical significance between liensinine protection group (6h) and liensinine protection group (24h); the comparison of CBF,CBV and MTT values had no (P>0.05)statistically significant between liensinine protection group (24h) and ischemic injury group (24h).In IP area we had performed the One-way ANOVA to the above data. The results of the analysis showed that the comparison of CBF and MTT values had statistical significance (P<0.05) between the Ischemia injury group(6h) and the control group,but the comparison of CBV value had no statistical significance (P>0.05). The comparison of CBF, MTT values between the liensinine protection group(6h) and the control group had statistical significance(P<0.05), but the comparison of CBV value had no statistical significance(P>0.05);The comparison of CBF,CBV and MTT values between liensinine protection group(6h) and the Ischemia injury group(6h) had no statistical significance (P>0.05);The comparison of CBF and CBV values between liensinine protection group(6h) and the Ischemia injury group(24h) had statistical significance (P<0.05), but the comparison of MTT value had no statistically significant(P>0.05); The comparison of CBF value between the ischemia injury group (6h) and the liensinine protection group(24h) had statistical significance(P<0.05), but the comparison CBV and MTT values had no statistically significant(P>0.05). The comparison of CBF and CBV values between he Ischemia injury group(24h) and liensinine protection group(24h) had statistical significance (P <0.05), but the comparison of MTT value had no statistical significance(P>0.05); The comparison of CBF,CBV and MTT values between the liensinine protection group(24h) and the control group had no statistically significant(P>0.05).Finally we had a comparison of the parameters under CTPI and the volume percentage of TTC staining area of brain ischemia between the ischemic injury group and liensinine protection group after reperfusing for24hours had statistical significance (P<0.05); The CBF value had statistical significance (P<0.05); CBV value had statistical significance (P<0.05); The MTT value had statistical significance (P<0.05). The infarction size of the liensinine protection group were smaller than the ischemia injury group, The ischemia area of pseudo-color images of CBF, CBV and MTT parameters and the infarction size were positively proportional increased, it was the CBV value that had a highest correlation.Conclusion:To establish the model of reperfusion injury of cerebral ischemic in rabbits,which are suit for examination of medical imaging equipments and for study;CT imaging of perfusion could accurately show the position and the size of cerebral infarction, could predict and evaluat the evolution process; the CBV and CBF value of the ischemic injury group after24hours were decreased than the value of the ischemic injury group after6hours, but the MTT value increased,which met priciple of reperfusion of breral ischemia;the CBV and CBF value of Liensinine protection group after24hours were increased than the value of the ischemic injury group after24hours, but the infarction size increased,all of these confirmed that Chinese medicine liensinine had significant protective effects on the rabbits with the model of reperfusion injury of cerebral ischemia.更多还原