Cui Yun-Liang, Wang Lv, Tian Zhao-Tao, Lin Zhao-Fen, Chen De-Chang
Department of Critical Care Medicine, Jinan Military General Hospital, Jinan, China.
Am J Chin Med. 2014;42(5):1215-27. doi: 10.1142/S0192415X14500761. Epub 2014 Sep 1.
The intestine plays a vital role in the pathophysiology of sepsis development. The objective of the present study was to explore the effects of rhubarb on intestinal microcirculation in septic rats. We used moorFLPI laser speckle imaging to detect the blood flow of the intestinal mucosa and wall. Using an ELISA, we assayed the concentration of lactate (L) and pyruvic acid (P) in the intestinal tissue to calculate the ratio of lactate to pyruvic acid (L/P ratio). To observe the intestinal mucosal capillaries, gelatin and ink were perfused into the intestine and subsequently stained with hematoxylin and eosin (HE) to measure the ratio of the vessel area. We then used immunohistochemistry to measure CD31 expression. Using an MTT assay, the effect of the rhubarb extract on the proliferation of human umbilical vein endothelial cells (HUVECs) was analyzed. The blood flow in the intestinal wall and mucosa of the control, sham and rhubarb-treated groups was significantly higher, while the sepsis group had relatively low blood flow. The L/P ratio in the intestinal tissue was larger in the sepsis group than in the other three groups. The microvascular area (MVA) in the sepsis group was smaller than in the control group, sham group or rhubarb group. Positive expression for CD31 was observed in the cytoplasm of vascular endothelial cells. The intestinal mucosal capillaries were reduced in septic rats as compared to the other three groups. HUVEC proliferation was enhanced by the rhubarb extract monomers at 1 μmol/L, but suppressed at higher concentrations of 10 to 100 μmol/L. These results suggest that pre-treatment with rhubarb prior to sepsis induction promotes the expansion of the intestinal mucosal capillaries, protects intestinal mucosal capillary endothelial cells and increases the number of functional intestinal capillaries.
肠道在脓毒症发生发展的病理生理学过程中起着至关重要的作用。本研究的目的是探讨大黄对脓毒症大鼠肠道微循环的影响。我们使用moorFLPI激光散斑成像技术检测肠黏膜和肠壁的血流情况。采用酶联免疫吸附测定法（ELISA）检测肠组织中乳酸（L）和丙酮酸（P）的浓度，以计算乳酸与丙酮酸的比值（L/P比值）。为观察肠黏膜毛细血管情况，将明胶和墨水灌注到肠道中，随后用苏木精和伊红（HE）染色以测量血管面积的比值。然后我们采用免疫组织化学法检测CD31的表达。运用MTT法分析大黄提取物对人脐静脉内皮细胞（HUVECs）增殖的影响。对照组、假手术组和大黄治疗组肠壁和肠黏膜的血流明显更高，而脓毒症组的血流相对较低。脓毒症组肠组织中的L/P比值大于其他三组。脓毒症组的微血管面积（MVA）小于对照组、假手术组或大黄组。在血管内皮细胞的细胞质中观察到CD31呈阳性表达。与其他三组相比，脓毒症大鼠的肠黏膜毛细血管减少。大黄提取物单体在1 μmol/L时可促进HUVEC增殖，但在10至100 μmol/L的较高浓度时则起抑制作用。这些结果表明，在诱导脓毒症之前用大黄预处理可促进肠黏膜毛细血管扩张，保护肠黏膜毛细血管内皮细胞，并增加功能性肠毛细血管的数量。
