摘要
目的:探讨脑死亡状态对巴马小型猪心脏结构与功能的影响及蛋白激酶C(PKC)在其发生机制中的作用。方法:巴马小型猪10只,随机分为脑死亡组与对照组,每组5只。应用改进的缓慢间断颅内加压法建立脑死亡模型,对照组仅开颅麻醉维持。于脑死亡后6、12和24 h检测血清中肌钙蛋白T(cTnT)、IL-1β、IL-6及TNF-α水平,24 h开胸取心肌组织,HE染色观察心脏组织结构变化,电镜观察心脏超微结构变化,免疫组化染色观察PKC-α蛋白表达,RT-PCR法检测PKC-αmRNA表达。结果:(1)心肌组织学变化:脑死亡后24 h可见心肌结构改变,光镜下见心内膜下片状出血,心肌溶解,断裂;电镜下见线粒体水肿,肌纤维模糊融合,嵴部分消失,膜部分融合。(2)血清cTnT变化:脑死亡组血清cTnT自脑死亡后6 h开始升高,并随时间延长而逐渐升高;各时点两组相比脑死亡组明显高于对照组(P<0.05)。(3)炎症介质变化:脑死亡组IL-1β、IL-6、TNF-α水平自6 h开始升高,并随时间延长而逐渐升高;各时点两组相比脑死亡组明显高于对照组(P<0.05)。(4)心肌细胞中PKC-αmRNA及其蛋白水平的变化:脑死亡组PKC-αmRNA及其蛋白表达水平均明显高于对照组(P<0.05)。结论:脑死亡导致巴马小型猪心脏结构与功能的损伤,炎症介质水平升高;脑死亡时心脏PKC-α表达水平升高。PKC-α的活化可能参与了脑死亡状态下心脏的损伤过程。
AIM: To investigate how brain - dead state affects the heart structure and function and the effect of PKC -α in BA - Ma mini pigs. METHODS : Ten Ba - Ma mini pigs were randomized into 2 groups : brain - dead group ( n = 5 ), and control group ( n = 5 ). The brain - dead model was made by increasing intracranial pressure, while the control group was maintained anesthesia for 24 h. The concentrations of cTnT, TNF -α, IL -1β and IL - 6 in serum were determined at 6, 12 and 24 h after brain death. At 24 h, heart tissues were observed by HE staining and electron microscope. The expression of PKC -α was detected by immunohistochemistry and RT - PCR. RESULTS : ( 1 ) Histological changes of myocardium: flaky bleeding under endocardium and dissolution of myocardium were found in optical microscope. In electron microscope dropsical mitochondria and confluent muscle fiber were found. (2) Changes of serum cTnT: serum cTnT for brain - dead group began to increase gradually since 6 h, and were significantly higher at each time point than those in control group ( P 〈 0. 05 ). ( 3 ) Changes of inflammatory factors : IL -1β, IL - 6, and TNF -α in brain - dead group began to increase gradually since 6 h, and were significantly higher at each time point than those in control group ( P 〈 0. 05 ). (4) Changes of PKC -α expression: PKC -α mRNA and protein expressions in brain - dead group increased significantly at 24 h ( P 〈 0. 05). CONCLUSION : Brain death may evoke heart structure and functional injury, and increase the levels of inflammatory factors and PKC -α. The activation of PKC -α may participate in the process of heart injury.
出处
《中国病理生理杂志》
CAS
CSCD
北大核心
2007年第8期1480-1483,共4页
Chinese Journal of Pathophysiology
关键词
巴马小型猪
脑死亡
蛋白激酶C
心脏损伤
Ba- Ma mini pigs
Brain death
Protein kinase C
Heart injuries