Disturbance of capillary perfusions due to leukocyte adhesion, disseminated intravascular coagulat ion, tissue edema is critical components in the pathophysiology of sepsis. Alterations in brain microcirculation during sepsis are not clearly understood. The aim of this study is to gain an improved understanding of alterations through direct visualization of brain microcirculations in an experimental endotoxemi a using intravital microscopy (IVM). Endotoxemia was induced in Lewis rats with Lipopolysaccharide (LPS, 15 mg/kg i.v.). The dura mater was removed via a cranial window to expose the pial vessels on the brain surface. Using fluorescence dyes, plasma extravasation of pial venous vessels and leukocyte-endothelial interaction were visualized by intravital microscopy 4 h after LPS administration. Plasma cytokine levels of IL1-β, IL-6, IFN-γ, TNF-α and KC/GRO were evaluated after IVM. A sign ificant plasma extravasation of the pial venous vessels was found in endotoxemia rats compared to control animals. In addition , a significantly increased number of leukocytes adherent to the pial venous endothelium was observed in septic animals. Endotoxemia also induced a significant elevation of plasma cytokine levels of IL1-β, IL-6, IFN-γ, TNF-α and KC/GRO. Endotoxemia increased permeability in the brain pial vessels accompanied by an increase of leukocyte-endothelium interactions and an increase of inflammatory cytokines in the plasma., J. Zhou ... [et al.]., and Obsahuje bibliografii a bibliografické odkazy
Rats received an injection of [14C]leucine and were then divided into four groups. Groups I and II consisted of ad libitum fed rats were administered saline or endotoxin of Salmonella enteritidis eight and twenty-two h after the [14C]leucine treatment. Animals of Group III (saline) and Group IV (endotoxin) fasted after [14C]leucine injection. Twenty three hours after [14C]leucine treatment rats were injected with pHjleucine and sacrificed 20 min afterwards. Endotoxin administration decreased body weight in fed rats only. After endotoxin treatment, higher [3H]leucine specific activity in the blood plasma, decreased leucine incorporation into proteins and lowered plasma amino acid levels were observed. [14C]leucine radioactivity was significantly higher in the spleen and lower in skeletal muscles of endotoxin-treated rats. All changes were less expressed in fasted than in ad libitum fed animals. Our results indicate that endotoxin treatment results in (a) changes in host metabolism that are not mediated solely by anorexia; (b) a decrease of protein synthesis in the viscera and skeletal muscles; (c) an increase of protein degradation in skeletal muscles; (d) reutilization of leucine released from skeletal muscles in viscera, and (e) a slower disappearance rate of leucine from the blood.
Fever developing after intracerebral injections of lipopolysaccharide (LPS) to guinea-pigs were monophasic, with only one peak of inner body temperature,slowly developing and longlasting in a dose range 20 to 200 ng of LPS. Latency time was inversely related to the dose of LPS. Indomethacin injected to the third brain ventricle did not abolish fever response.