STEROID ACTION IN BACTERIAL ENDOTOXIC SHOCK

细菌内毒素休克中的类固醇作用

• 批准号: 3129902
• 负责人: RODERICK E MCCALLUM
• 金额: $ 4.25万
• 依托单位: UNIVERSITY OF OKLAHOMA HLTH SCIENCES CTR
• 依托单位国家: 美国
• 财政年份: 1984
• 资助国家: 美国
• 起止时间: 1984-03-01 至 1987-02-28
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/3129902
• 关键词: Escherichia coli; Kupffer's cell; adrenalectomy; carbohydrate metabolism; cell free system; dexamethasone; endotoxins; glucocorticoids; gluconeogenesis; gram negative bacteria; hormone regulation /control mechanism; host organism interaction; hypoglycemia; kidney; liver cells; liver metabolism; molecular pathology; spleen; steroid hormone metabolism; striated muscles

Bacterial endotoxins (ETX), components of the cell wall of gram-negative bacteria, elicit a number of cardiovascular, inflammatory, and hormonal responses. ETX-mediated alterations in metabolism, including glycogen depletion and diminished gluconeogenesis, occur at a time when plasma glucocorticoid, glucogan and epinephrine levels are normal to elevated. Our overall objective is to determine the mechanism(s) by which ETX perturbs host carbohydrate metabolism during gram-negative speticemia. This study is based on the hypothesis that ETX interferes with the normal action of glucocorticoids at the molecular level. To examine this hypothesis, we propose to investigate the consequences of down regulation of glucocorticoid receptors during endotoxemia. We will extend preliminary studies by comparing glucocorticoid binding to liver, spleen, skeletal muscle, and kidney cytosolic receptors from ETX-treated mice. We will determine whether the effects of ETX on cytosolic binding are direct or mediated by adding ETX directly to isolated normal hepatocytes in vitro, and with the passive transfer of serum and peritoneal cells between ETX-normal responder mice and ETX-low responder mice. Soluble mediators that may regulate hepatic glucocorticoid receptors will be screened for, using cultured peritoneal exudate cells and isolated Kupffer cells. Purification and characterization of soluble factors found to regulate steroid receptors will be pursued. A secondary aim of this study is to examine other aspects of intracellular steroid action in liver during endotoxic shock. We will determine the magnitude of nuclear binding of steroid-protein complexes in liver (in vivo) and in hepatocyte (in vitro) preparations. RNA polymerase activity will be measured, as will the ability of mRNA isolated from endotoxin-treated and control mouse livers to direct protein synthesis in a cell-free translation system. Successful completion of this study will yield data describing whether interference with glucocorticoid action in liver ETX is direct or mediated. In addition, the project will ultimately lead to an understanding of the role of altered hepatic metabolism in bacterial sepsis and shock.

革兰阴性杆菌细胞壁成分细菌内毒素(ETX) 细菌，引发许多心血管、炎症和荷尔蒙 回应。ETX介导的代谢改变，包括糖原 耗竭和糖异生减少，发生在血浆 糖皮质激素、高血糖素和肾上腺素水平正常到升高。 我们的总体目标是确定ETX通过什么机制(S) 在革兰氏阴性菌血症期间扰乱宿主碳水化合物代谢。 这项研究是基于ETX干扰正常的 糖皮质激素在分子水平的作用。要检查这一点 假设，我们建议研究下调监管的后果。 内毒素血症时糖皮质激素受体的变化。我们将延长初步的 糖皮质激素与肝、脾、骨骼结合的比较研究 ETX处理的小鼠的肌肉和肾脏胞质受体。我们会 确定ETX对胞质结合的影响是直接的还是 通过在体外分离的正常肝细胞中直接加入ETX， 随着血清和腹膜细胞之间的被动转移 ETX-正常应答小鼠和ETX-低应答小鼠。可溶性调停物 可能调节肝脏糖皮质激素受体的基因将被筛选出来， 使用培养的腹膜渗出细胞和分离的Kupffer细胞。 可溶性调节因子的分离纯化及性质研究 类固醇受体将被追踪。这项研究的第二个目的是 检查肝脏细胞内类固醇作用的其他方面 内毒素休克。我们将确定核结合的大小 肝脏(体内)和肝细胞(体外)中的类固醇蛋白复合体 准备工作。RNA聚合酶活性将被测量， 内毒素处理小鼠肝脏和对照小鼠肝脏中提取的信使核糖核酸的活性 在无细胞翻译系统中直接合成蛋白质。成功 这项研究的完成将产生描述干扰是否 ETX在肝脏中具有糖皮质激素的作用，是直接的或中介的。在……里面 此外，该项目最终将导致对角色的理解 细菌性败血症和休克时肝脏代谢的改变。