Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0004610 (bacteremia)
 13,199 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Recruitment of inflammatory cells to the lung capillaries has been proposed as an important step in the sequence of events that lead to acute lung injury. Frequently, in the clinical setting, bacteremia and sepsis syndrome precede the acute lung failure and endotoxin priming may represent a comparable paradigm, useful for experimental pursuit. Following addition of the chemotactic tripeptide FMLP (10(-9) to 10(-6) M) to the cell-free, salt solution perfusate of isolated rat lungs, only a small degree of vasoconstriction was observed. However, in lungs isolated from rats that received 2 mg/kg intraperitoneal Salmonella enteritidis endotoxin 2 h before lung perfusion, FMLP dose dependently caused a large, transient pulmonary pressor response, edema formation, and release of large amounts of thromboxane and leukotriene B4. Since in vitro priming with endotoxin, direct vascular injury by neutrophil elastase, nor direct stimulation with FMLP of pulmonary artery rings from endotoxin-pretreated rats, mimicked the effects of in vivo endotoxin priming, we conclude that the presence of inflammatory cells in the lung capillaries accounted for the large amount of eicosanoids produced by the lungs after FMLP stimulation. In fact, by retrograde lavage of the lung circulation with a collagenase solution, previously adherent cell clumps were mobilized and identified. These cell clumps, composed of red blood cells, neutrophils, and platelets, were not seen in the vascular lavage sediment obtained from unprimed control lungs. Indomethacin, a thromboxane antagonist, AA861, a 5-lipoxygenase inhibitor, and WEB 2086, a platelet-activating factor (PAF) antagonist, reduced the thromboxane synthesis and release after FMLP (10(-7) M) in in vivo endotoxin-primed lungs. None of the inhibitors employed exclusively inhibited only one particular eicosanoid mediator but rather affected the release of several mediators, suggesting a close link between the different synthetic arachidonic acid pathways. An inhibitor of phospholipase C (2-nitro-4-carboxyphenyl-N,N-diphenylcarbamate), NCDC, but not an inhibitor of phospholipase D (Wortmannin) or of protein kinase C (staurosporine) inhibited the FMLP-stimulated pulmonary pressure rise and eicosanoid release in endotoxin-primed lungs in vivo. Our data suggest that eicosanoids (in particular thromboxane) released from cells trapped in the lung circulation, but not from constitutive lung cells, contribute to vasoconstriction and edema formation caused by the chemoattractant FMLP in endotoxin-primed lungs.
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PMID:FMLP causes eicosanoid-dependent vasoconstriction and edema in lungs from endotoxin-primed rats. 154 53

The effects of selectively inhibiting synthesis of thromboxane A2 (TXA2) with dazoxiben and of all cyclooxygenase products with indomethacin were studied in goats after infusion of 5 X 10(8) live Escherichia coli bacteria/kg. Pulmonary and systemic pressures, cardiac output, and double indicator dilution extravascular lung water (EVLW) were measured at 15-min intervals. EVLW was determined gravimetrically at 6 hr to confirm the final double indicator dilution values. Plasma levels of TXA2 and prostacyclin (PGI2) were measured as their stable metabolites, TXB2 and 6-keto-PGF1 alpha, respectively. Dazoxiben blocked the increase in plasma TXB2, prevented pulmonary hypertension, and attenuated the increase in EVLW after E. coli. Mean gravimetric EVLW was 8.7 ml/kg in the dazoxiben-treated group compared to 11.3 ml/kg in the untreated control group. Indomethacin blocked the increased plasma TXB2 and 6-keto-PGF1 alpha, attenuated pulmonary hypertension, and prevented almost all increases in EVLW. Mean gravimetric EVLW was 8.2 ml/kg after indomethacin. We conclude that in acute bacteremia, the early pulmonary hypertension is mediated largely by TXA2 (however, a second phase of hypertension results from non-cyclooxygenase products), either production of cyclooxygenase products (perhaps PGI2) inhibits part of the action of pulmonary vasoconstrictors, or indomethacin stimulates the production of other vasoconstrictors (such as lipoxygenase products), and indomethacin prevents the accumulation of EVLW by blocking formation of cyclooxygenase products or by other nonspecific actions.
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PMID:Indomethacin, dazoxiben and extravascular lung water after Escherichia coli infusion. 309 72

The nonsteroidal anti-inflammatory drugs, indomethacin and ibuprofen, have been shown to increase survival in various animal models of Gram-negative or endotoxin shock. To evaluate the use of these drugs in group B streptococcal sepsis, a clinically similar disease state, a newborn suckling rat model (4 to 5 days old) designed to simulate early-onset group B streptococcal sepsis was used. Sepsis was induced by a subcutaneous injection of group B streptococcal organisms (type III). A mortality ranging from 30% to 90% was used for the study. Indomethacin (3 mg/kg) or ibuprofen (4 mg/kg) treatment was administered by an intraperitoneal injection either at the time of the bacterial injection or after bacteremia (four hours) had occurred. Indomethacin clearly improved survival rates, even when given after bacteremia. Ibuprofen also clearly increased survival when given at the same time as the bacterial injection. Ibuprofen was more effective than indomethacin in the high mortality model (lethal dose for 90% survival of group). These drugs alter mechanisms that may be important in the irreversibility of sepsis and they may become useful adjuvants to our present treatment of early onset group B streptococcal sepsis.
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PMID:Improved survival in the suckling rat model of group B streptococcal sepsis after treatment with nonsteroidal anti-inflammatory drugs. 705 Aug 75

We tested the hypothesis that gram-negative bacteremia (GNB) and brief (30 min) reductions in the hepatic O2 supply by low-flow ischemia differentially modulate tumor necrosis factor-alpha (TNF-alpha) gene expression owing to sequence-specific activation of cyclooxygenase vs. complement (C) pathways. Buffer-perfused Sprague-Dawley rat livers (n = 82) were studied over 180 min after intraportal 10(9) live E. coli serotype 055:B5 (EC) or 0.9% NaCl (NS) at t = 0. Compared with EC and NS controls receiving constant-flow perfusion, sequential GNB and ischemia/reperfusion (I/R) were studied in EC + 30 I/R and NS + 30 I/R livers, in which 30 min of ischemia (I) beginning 0.5 h after EC or NS was followed by 120 min of reperfusion (R). This sequence was reversed in 30 I/R + EC and 30 I/R + NS groups. Bacterial clearance, bioactive and antigenic TNF-alpha, prostaglandin E2 (PGE2), and hepatic O2 uptake and performance were serially assessed. Venous TNF-alpha increased in EC controls to peak at 155 +/- 29 U/ml after 180 min (P < 0.001 vs. NS controls) as did hepatic TNF-alpha mRNA. Both TNF-alpha transcripts and protein levels were markedly attenuated in EC + 30 I/R (P < 0.001 vs. EC) despite equivalent EC clearance by Kupffer cells. Indomethacin (10(-5) M) decreased I/R-induced PGE2 secretion and restored TNF-alpha to control levels. In contrast, TNF-alpha levels in 30 I/R + EC perfusates exceeded those of EC + 30 I/R livers (P < 0.05) and were indistinguishable from EC controls. Allopurinol pretreatment but not heat inactivation of C or infusion of soluble human complement receptor type 1 inhibited TNF-alpha production in 30 I/R + EC organs. These results identify a novel sequence-dependent interaction whereby hepatic O2 deprivation after GNB downregulates TNF-alpha via generation of cyclooxygenase metabolites, whereas ischemia preceding GNB increases cytokine expression via reactive O2 species but not C activation.
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PMID:Bidirectional effects of hepatic ischemia/reperfusion on E. coli-induced TNF-alpha gene expression. 876 13