十二井穴刺络放血联合亚低温治疗对颅脑创伤急性期大鼠脑水肿的影响

Therapeutic bloodletting at Jing-well points combine hypothermia attenuated acute cerebral edema after traumatic brain injury in rats

目的:探讨十二井穴刺络放血联合亚低温对颅脑创伤(TBI)大鼠急性期脑水肿的影响。方法:将75只健康成年雄性SD大鼠随机分为5组(n=15):假手术组(Sham)、颅脑创伤组(TBI)、放血组(BL)、亚低温组(MIH)、放血联合亚低温组(BL+MIH)。采用电子脑皮质损伤撞击仪(eCCI)建立大鼠TBI模型,BL组于伤后即刻行十二井穴刺络放血,每日2次;MIH组在伤后即刻采用亚低温冰毯使体温降至32℃,持续干预6 h。伤后48 h分别采用核磁共振成像技术(MRI)观察脑水肿变化(n=3)、神经功能缺损评分(m NSS)观察行为学改变及干/湿重法测定脑含水量(n=8)、伊文思蓝染色(EB)检测血脑屏障通透性(BBB)(n=4)。结果:MRI显示,TBI组脑水肿及血肿明显,中线明显偏移;而干预组较TBI组水肿明显减轻,中线居中。与TBI组比较,各干预组m NSS评分均明显改善(P<0.05),而且BL+MIH组优于单独BL和MIH组(均P<0.01);各干预组脑含水量也有不同程度降低(P<0.05),尤以MIH组和BL+MIH组降低最为显著(P<0.01);各干预组血脑屏障通透性均有明显改善(均P<0.01),而且MIH组和BL+MIH组显著优于单独BL组(P<0.05,P<0.01)。结论:十二井穴刺络放血和亚低温均可以降低神经功能缺陷评分,减轻脑水肿,降低血脑屏障通透性,对创伤性大鼠脑组织有保护作用,且二者联合治疗效果更加明显。

Objective： To investigate the influence of therapeutic bloodletting at Jing-well points and hypothermia on acute cerebral edema after traumatic brain injury （TBI） in rats. Methods： Seventy-five SD rats were randomly divided into sham-operation group （Sham）, TBI group （TBI）, bloodletting group （BL）, mild-induced hypothermia group （MIH）, and bloodletting plus MIH group （BL ＋ MIH）（ n = 15）. The model of TBI was established by electric controlled cortical impactor （eCCI）. The rats of BL group were bloodletting at Jing-well points im- mediately after injury, twice daily. While the MIH group was settled on a hypothermia blanket promptly after TBI for 6 hours, so that the tem- perature dropped to 32 degrees. Each of measurement was performed after 48 hours. Magnetic resonance imaging （MRI） was used to evaluate the dynamic impairment of cerebral edema after TBI （ n = 3）. In addition, mNSS score, measurements of wet and dry brain weight, and Evans Blue assay were performed to investigate the neurologic deficit, cerebral water content （n = 8）, and blood-brain barrier permeability（BBB）, （ n = 4）, respectively. Results： MRI analysis showed that the cerebral edema, hematoma and midline shifting of rats in TBI group was more serious than other treatment group. Meanwhile compared with TBI group, the mNSS scores of every treatment group were meaningfully lower （all P 〈 0.05）. Furthermore, treatment with BL ＋ MIH group was superior to the separated BL and MIH group （all P 〈 0.01 ）. In addition, brain water content of each intervention group reduced to varying degrees （ all P 〈 0.05）, especially that of MIH group and BL ＋ MIH group （ P 〈 0.01）. BBB permeability of each treatment group was also significantly improved （all P 〈 0. 01 ）, and the improvement in MIH group and BL ＋ MIH group was much better than the BL alone group （ P 〈 0.05, P 〈 0. 01 ）. Conclusion： Our major finding is that bloodletting at Jing-well points and MIH can reduce cerebral edema and BBB dysfunction and exert neuroprotective effects after TBI. The results suggest that the combination of BL and MIH is more effective than other treatment being used alone.