In vivo analysis of intestinal permeability following hemorrhagic shock.
In vivo analysis of intestinal permeability following hemorrhagic shock.
复制标题
DOI：
10.5492/wjccm.v4.i4.287
复制
发表时间：
2015-11-04
期刊：
影响因子：
--
通讯作者：
Kistler, Erik B
中科院分区：
文献类型：
--
作者：
Alsaigh, Tom;Chang, Marisol;Kistler, Erik B
目的：为了确定肠通透性的变化，以proteolytically衍生的肠肽在实验性hemorrhagic shock.METHODS：我们注射荧光共轭酪蛋白到麻醉Wistar大鼠的小肠诱导实验性失血性休克前的时间过程。这些分子在蛋白水解裂解时发荧光，被用作蛋白水解裂解的肠产物进入中央循环能力的标志物。连续采集血液样本，以定量体循环中蛋白水解裂解颗粒浓度的相对变化。为了提供其位置的空间分辨率，使用活体荧光显微镜对肠系膜微血管中的颗粒进行成像。然后使用另一种测量技术，异硫氰酸荧光素（FITC）标记的葡聚糖20重复实验，以半定量地验证肠源性低分子量分子（< 20 kD）进入中央循环的能力。结果表明，在诱导出血后20分钟内，肠源性肽的全身渗透性显著增加（1.11 ± 0.19 vs 0.86 ± 0.07，P < 0.05）。与对照组相比，再灌注导致老化动物对肠源性肽的全身渗透性第二次持续增加（1.2 ± 0.18 vs 0.97 ± 0.1，P < 0.05）。肠系膜活体显微镜检查也显示，与对照组相比，老年动物的微循环中荧光颗粒明显积聚。使用FITC dextrans 20复制这些结果[10.85 ± 6.52 vs 3.38 ± 1.11荧光强度单位（* 10（5），P < 0.05，失血性休克vs对照）]，证实了响应于实验性失血性休克的小肠缺血导致肠膜通透性的显著和早期增加。出血性休克时小肠通透性增加可能会使蛋白水解产生的肽被全身吸收，从而导致血流动力学不稳定和远端器官衰竭。
AIM: To determine the time course of intestinal permeability changes to proteolytically-derived bowel peptides in experimental hemorrhagic shock.METHODS: We injected fluorescently-conjugated casein protein into the small bowel of anesthetized Wistar rats prior to induction of experimental hemorrhagic shock. These molecules, which fluoresce when proteolytically cleaved, were used as markers for the ability of proteolytically cleaved intestinal products to access the central circulation. Blood was serially sampled to quantify the relative change in concentration of proteolytically-cleaved particles in the systemic circulation. To provide spatial resolution of their location, particles in the mesenteric microvasculature were imaged using in vivo intravital fluorescent microscopy. The experiments were then repeated using an alternate measurement technique, fluorescein isothiocyanate (FITC)-labeled dextrans 20, to semi-quantitatively verify the ability of bowel-derived low-molecular weight molecules (< 20 kD) to access the central circulation.RESULTS: Results demonstrate a significant increase in systemic permeability to gut-derived peptides within 20 min after induction of hemorrhage (1.11 ± 0.19 vs 0.86 ± 0.07, P < 0.05) compared to control animals. Reperfusion resulted in a second, sustained increase in systemic permeability to gut-derived peptides in hemorrhaged animals compared to controls (1.2 ± 0.18 vs 0.97 ± 0.1, P < 0.05). Intravital microscopy of the mesentery also showed marked accumulation of fluorescent particles in the microcirculation of hemorrhaged animals compared to controls. These results were replicated using FITC dextrans 20 [10.85 ± 6.52 vs 3.38 ± 1.11 fluorescent intensity units (* 10(5), P < 0.05, hemorrhagic shock vs controls)], confirming that small bowel ischemia in response to experimental hemorrhagic shock results in marked and early increases in gut membrane permeability.CONCLUSION: Increased small bowel permeability in hemorrhagic shock may allow for systemic absorption of otherwise retained proteolytically-generated peptides, with consequent hemodynamic instability and remote organ failure.