Miranda Celina Teresa Castelo Branco Couto de, Fagundes Djalma José, Miranda Edinaldo de, Simões Ricardo Santos, Carbonel Adriana Aparecida Ferraz, Florencio-Silva Rinaldo, Taha Murched Omar
Medical School, Universidade Estadual do Piauí, Teresina, PI, Brazil.
Division of Surgical Techniques and Experimental Surgery, Department of Surgery, Universidade Federal de São Paulo, Brazil.
Acta Cir Bras. 2019;34(5):e201900501. doi: 10.1590/s0102-865020190050000001. Epub 2019 Jun 3.
To analyze the effects of ischemic preconditioning (IPC) in the expression of apoptosis-related genes in rat small intestine subjected to ischemia and reperfusion.
Thirty anesthetized rats underwent laparotomy and were drive into five groups: control (CG); ischemia (IG); ischemia and reperfusion (IRG); IPC and ischemia (IG+IPC); IPC and ischemia and reperfusion (I/RG+IPC). Intestinal ischemia was performed by clamping the superior mesenteric artery for 60 minutes, whereas reperfusion lasted for 120 minutes. IPC was carried out by one cycle of 5 minutes of ischemia followed by 10 minutes of reperfusion prior to the prolonged 60-minutes-ischemia and 120-minutes-reperfusion. Thereafter, the rats were euthanized and samples of small intestine were processed for histology and gene expression.
Histology of myenteric plexus showed a higher presence of neurons presenting pyknotic nuclei and condensed chromatin in the IG and IRG. IG+IPC and I/RG+IPC groups exhibited neurons with preserved volume and nuclei, along with significant up-regulation of the anti-apoptotic protein Bcl2l1 and down-regulation of pro-apoptotic genes. Moreover, Bax/Bcl2 ratio was lower in the groups subjected to IPC, indicating a protective effect of IPC against apoptosis.
Ischemic preconditioning protect rat small intestine against ischemia/reperfusion injury, reducing morphologic lesions and apoptosis.
分析缺血预处理（IPC）对大鼠小肠缺血再灌注后凋亡相关基因表达的影响。
30只麻醉大鼠行剖腹术，分为五组：对照组（CG）；缺血组（IG）；缺血再灌注组（IRG）；IPC与缺血组（IG+IPC）；IPC与缺血再灌注组（I/RG+IPC）。通过夹闭肠系膜上动脉60分钟造成肠缺血，再灌注持续120分钟。IPC通过在延长的60分钟缺血和120分钟再灌注之前进行一个5分钟缺血随后10分钟再灌注的周期来实施。此后，对大鼠实施安乐死，并对小肠样本进行组织学和基因表达处理。
肌间神经丛组织学显示，IG组和IRG组中出现核固缩和染色质凝聚的神经元较多。IG+IPC组和I/RG+IPC组的神经元体积和细胞核保存良好，抗凋亡蛋白Bcl2l1显著上调，促凋亡基因下调。此外，接受IPC的组中Bax/Bcl2比值较低，表明IPC对细胞凋亡有保护作用。
缺血预处理可保护大鼠小肠免受缺血/再灌注损伤，减少形态学损伤和细胞凋亡。
