INTESTINAL PERFUSION AND PERMEABILITY IN SEPSIS

描述：(改编自申请者的摘要)本次比赛 更新应用的基础是假设肠道上皮 细胞酸中毒导致屏障功能紊乱。在当前 研究人员资助的研究表明，回肠粘膜酸中毒 在猪体内增加了粘膜的通透性，暴露于 粘膜细胞(Caco-2BBe)对酸的单层也诱导增加 体外上皮通透性。调查员的研究还包括 研究表明，酸中毒会促进脂质过氧化，增加细胞内 Fe2，并部分耗尽Caco-2Be肠上皮细胞内的ATP。 这些研究还表明，抑制钙蛋白酶和 磷脂酶可改善酸诱导的粘膜高通透性。 这些研究共同支持细胞内 钙相关的紊乱可能在酸中毒的发病机制中起重要作用 诱导粘膜屏障功能障碍。目前的提议将延长 Caco-2BBe细胞和单核细胞的研究：1)测量 细胞内[H]，2)评估酸中毒和三磷酸腺苷的影响 内皮细胞对水溶性大分子AS通透性的耗竭 以及可吸入颗粒物，如细菌脂多糖和大肠杆菌。在……里面 此外，该提案将侧重于细胞骨架的完整性及其 酸中毒与粘膜细胞通透性障碍的关系 在Caco-2BBe单层中。研究还将评估 肠细胞酸中毒或中度ATP耗竭对[钙]i的影响，以及 A23187、BAPTA及不同磷脂酶修饰剂的作用 钙蛋白水解酶和蛋白激酶C在酸性和/或低水平三磷酸腺苷诱导的粘膜中的作用 通透性功能障碍。上述所有研究都将是 Caco-2BBe细胞系体外携带。最后，实验将 确定回肠粘膜通透性的各种决定因素 失血性损伤大鼠体内研究中的功能障碍。 这些研究将采用体内方法学来确定两者 脂多糖易位与大分子回肠通透性 上皮组织。

DESCRIPTION: (Adapted from the applicant's abstract) This competing renewal application is based on the hypothesis that gut epithelial barrier function is deranged by cellular acidosis. In the currently funded research, the investigator has shown that ileal mucosal acidosis in pigs increases mucosal permeability in vivo, and that exposure of mucosal cell (CaCo-2BBe) monolayers to acid also induce an increase in epithelial permeability in vitro. The investigator's studies have also shown that acidosis promotes lipid peroxidation, increases intracellular Fe2+, and partly depletes cellular ATP in the CaCo-2BBe enterocytes. These studies have demonstrated also that inhibition of calpain and phospholipases ameliorated acid induced mucosal hyperpermeability. These studies collectively support the concept that intracellular calcium related derangements may be important in the pathogenesis of acid induced mucosal barrier dysfunction. The present proposal will extend the studies of CaCo-2BBe cells and monocytes by: 1) measuring intracellular [H+], 2) assessing the effect of acidosis and ATP depletion on epithelial permeability to water soluble macromolecule as well as to particulate matter such as LPS and E.coli bacteria. In addition the proposal will focus on cytoskeletal integrity and its relationship to acidosis induced mucosal cell permeability dysfunction in CaCo-2BBe monolayers. Studies will evaluate also the effect of acidosis or moderate ATP depletion in the enterocytes on [Ca2+]i, and the effects of A23187, BAPTA, and various modifiers of phospholipases calpains and PKC on the acid and/or low ATP level induced mucosal permeability dysfunction. all of the aforementioned studies are to be carrier in the CaCo-2BBe cell line in vitro. Finally, experiments will ascertain the various determinants of ileal mucosal permeability dysfunction in the in vivo studies in a rat model of hemorrhagic injury. These studies will employ in vivo methodology to determine both translocation of LPS and permeability of macromolecules across the ileal epithelium.