Critical Care

, 4:P43 | Cite as

Effects of epinephrine and norepinephrine on endotoxin-induced tissue factor expression in blood monocytes

  • L de Rossi
  • T Scholz
  • T Eckermann
  • U Temmler
  • S Ruβurm
  • K Reinhart
  • W Lösche
Meeting abstract
  • 912 Downloads

Keywords

Tissue Factor Tissue Factor Expression Monocyte Activity Whole Blood Whole Blood Sample 

Full text

Background

Tissue factor (TF) is the most important initiator of intravascular coagulation. In monocytes the expression of pro-inflammatory cytokines and TF is controlled by the same transcription factors. Catecholamines, frequently used in sepsis therapy of critically ill patients, have been shown to inhibit endotoxin-induced expression of monocyte cytokines, such as TNF-α or IL-6 [1]. The aim of our study was to prove whether epinephrine (EPI) and norepinephrine (NOREPI) may also affect TF expression.

Methods

To induce TF and TNF-α expression in monocytes we incubated citrated human whole blood (WB) for four hours with LPS (E. coli 055:B5; 50 ng/ml). TF expression on monocytes was determined by flow cytometry, TNF-α secretion was measured by ELISA.

Results

Incubating WB samples with 50 ng/ml LPS we observed an increase in the number of TF-positive monocytes from 3.9± 0.7% to 42.9± 2.8%. 5.5 nM EPI inhibited LPS-induced TF expression by about 16% (P=0.03), but the inhibitory effect was attenuated at higher EPI concentrations (>550 nM). LPS-induced TNF-α secretion (4.2± 0.5 ng/ml) was inhibited by about 60% in presence of 5.5 nM EPI, and maximum inhibition of 75% was reached at 55 nM. Compared to EPI, higher concentrations of NOREPI were needed to get a significant inhibition of monocyte activity. Inhibition of TF-expression by 13% was observed at 550 nM and the same inhibition was observed at 5,500 nM. TNF-α secretion was inhibited in a clear dose-dependent manner and amounted at 5.5 nM NOREPI to about 35% and at 5500 nM to about 75%.

Conclusion

EPI is more effective than NOREPI to inhibit LPS-induced monocyte TF expression and TNF-α secretion. At higher concentrations EPI also seemed to have a stimulatory effect on TF expression, which could be due to an interaction of EPI-activated platelets [2] with monocytes.

References

  1. 1.
    van der Poll , et al.: . Infect Immunol 1994, 62: 2046-2050.Google Scholar
  2. 2.
    Amirkhosravi , et al.: . Thromb Haemost 1996, 75: 87-95.Google Scholar

Copyright information

© Current Science Ltd 2000

Authors and Affiliations

  • L de Rossi
    • 1
  • T Scholz
    • 3
  • T Eckermann
    • 2
  • U Temmler
    • 3
  • S Ruβurm
    • 2
  • K Reinhart
    • 2
  • W Lösche
    • 3
  1. 1.Clinic of AnaesthesiologyRheinisch-Westfälische Technische Hochschule AachenAachenGermany
  2. 2.Clinic of Anaesthesiology and Intensive Care TherapyFriedrich-Schiller-UniversityJenaGermany
  3. 3.Centre for Vascular Biology and Medicine/ErfurtFriedrich-Schiller-UniversityJenaGermany

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