Nitric oxide measurements during endotoxemia.

BACKGROUND Excessive continuous NO release from inducible NO synthase over prolonged periods under pathological conditions, such as endotoxemia, contributes significantly to circulatory failure, hypotension, and septic shock. This NO production during endotoxemia is accompanied by superoxide release, which contributes to the fast decay of NO. Therefore, the amount of NO that diffuses to target sites may be much lower than the total amount released under pathological conditions. METHODS We performed in vivo and ex vivo measurements of NO (electrochemical) and ex vivo in situ measurements of superoxide, peroxynitrite (chemiluminescence), and nitrite and nitrate (ultraviolet-visible spectroscopy). We determined the effect of lipopolysaccharide administration (20 mg/kg) on diffusible NO, total NO (diffusible plus consumed in chemical reactions), and superoxide and peroxynitrite release in the pulmonary arteries of rats. RESULTS An increase in diffusible NO generated by constitutive NO synthase was observed immediately after administration of lipopolysaccharide, reaching a plateau (145 +/- 18 nmol/L) after 540 +/- 25 s. The plateau was followed by a decrease in NO concentration and its subsequent gradual increase after 45 min because of NO production by inducible NO synthase. The concentration of superoxide increased from 16 +/- 2 nmol/L to 30 +/- 3 nmol/L after 1 h and reached a plateau of 41 +/- 4 nmol/L after 6 h. In contrast to the periodic changes in the concentration of diffusible NO, the total concentration of NO measured as a sum of nitrite and nitrate increased steadily during the entire period of endotoxemia, from 2.8 +/- 0.2 micromol/L to 10 +/- 1.8 micromol/L. CONCLUSIONS The direct measurement of NO concentrations in the rat pulmonary artery demonstrates dynamic changes throughout endotoxemia, which are related to the production of superoxide and the subsequent increase in peroxynitrite. Monitoring endotoxemia with total nitrate plus nitrite is not sensitive to these fluctuations in NO concentration.

[1]  D. Annane,et al.  Compartmentalised inducible nitric-oxide synthase activity in septic shock , 2000, The Lancet.

[2]  M. Nakamura,et al.  The cardiovascular effects and implications of peroxynitrite. , 1999, Cardiovascular research.

[3]  D. Kwiatkowski,et al.  Nitric oxide and infectious diseases , 1999, Archives of disease in childhood.

[4]  M. Titheradge.  Nitric oxide in septic shock. , 1999, Biochimica et biophysica acta.

[5]  K. Kröncke,et al.  Inducible nitric oxide synthase in human diseases , 1998, Clinical and experimental immunology.

[6]  B. Mayer,et al.  Nitric oxide synthases: catalytic function and progress towards selective inhibition , 1998, Naunyn-Schmiedeberg's Archives of Pharmacology.

[7]  T. O’Brien,et al.  Transfer and expression of recombinant nitric oxide synthase genes in the cardiovascular system. , 1998, Trends in pharmacological sciences.

[8]  G. Ellis,et al.  Nitrite and nitrate analyses: a clinical biochemistry perspective. , 1998, Clinical biochemistry.

[9]  S. Hollenberg.  Inhibition of nitric oxide synthesis in sepsis: a promising strategy? , 1998, Critical care medicine.

[10]  S. James,et al.  Nitric oxide in health and disease , 1998, Nature Medicine.

[11]  J. Parratt.  Nitric oxide. A key mediator in sepsis and endotoxaemia? , 1997, Journal of physiology and pharmacology : an official journal of the Polish Physiological Society.

[12]  G. Burnstock,et al.  Nitric Oxide in Health and Disease , 1997 .

[13]  D. Pinsky,et al.  Mechanical transduction of nitric oxide synthesis in the beating heart. , 1997, Circulation research.

[14]  L. Engstrand,et al.  Urinary nitrite: more than a marker of infection. , 1997, Urology.

[15]  U. Losert,et al.  L-arginine treatment alters the kinetics of nitric oxide and superoxide release and reduces ischemia/reperfusion injury in skeletal muscle. , 1997, Circulation.

[16]  A. Ueda,et al.  A novel nonenzymatic pathway for the generation of nitric oxide by the reaction of hydrogen peroxide and D- or L-arginine. , 1997, Biochemical and biophysical research communications.

[17]  T. Malinski,et al.  Determination of nitric oxide saturated (stock) solution by chronoamperometry on a porphyrine microelectrode , 1997 .

[18]  M. Modolell,et al.  Oxidation of N G‐hydroxyl‐l‐arginine to nitric oxide mediated by respiratory burst: an alternative pathway to NO synthesis , 1997, FEBS letters.

[19]  G. Entlicher,et al.  Possible mechanism of nitric oxide production from N(G)-hydroxy-L-arginine or hydroxylamine by superoxide ion. , 1996, The international journal of biochemistry & cell biology.

[20]  J. Zweier,et al.  Measurement of Nitric Oxide and Peroxynitrite Generation in the Postischemic Heart , 1996, The Journal of Biological Chemistry.

[21]  J S Beckman,et al.  Nitric oxide, superoxide, and peroxynitrite: the good, the bad, and ugly. , 1996, The American journal of physiology.

[22]  F. Kiechle,et al.  Indirect detection of nitric oxide effects: a review. , 1996, Annals of clinical and laboratory science.

[23]  J. Young,et al.  Effect of renal function on serum nitrogen oxide concentrations. , 1996, Clinical chemistry.

[24]  Martin Feelisch,et al.  Methods in nitric oxide research , 1996 .

[25]  S. Moncada,et al.  Direct measurement of nitric oxide in human beings , 1995, The Lancet.

[26]  H. Redl,et al.  Shock, Sepsis, and Organ Failure — Nitric Oxide , 1995, Springer Berlin Heidelberg.

[27]  T. Malinski,et al.  Light-activated release of nitric oxide from vascular smooth muscle of normotensive and hypertensive rats. , 1994, Biochemical and biophysical research communications.

[28]  S Moncada,et al.  Nitric oxide synthases in mammals. , 1994, The Biochemical journal.

[29]  R. Weiss,et al.  Nitric oxide synthase: an endogenous source of elevated nitrite in infected urine. , 1994, Kidney international.

[30]  P. Klatt,et al.  Multiple catalytic functions of brain nitric oxide synthase. Biochemical characterization, cofactor-requirement, and the role of N omega-hydroxy-L-arginine as an intermediate. , 1993, The Journal of biological chemistry.

[31]  T. Malinski,et al.  Nitric oxide release from a single cell measured in situ by a porphyrinic-based microsensor , 1992, Nature.

[32]  F. Ognibene,et al.  Septic shock in humans. Advances in the understanding of pathogenesis, cardiovascular dysfunction, and therapy. , 1990, Annals of internal medicine.

[33]  H. Gyllenhammar,et al.  Lucigenin chemiluminescence in the assessment of neutrophil superoxide production. , 1987, Journal of immunological methods.

[34]  T. Sandberg,et al.  Plasma nitrate as an index of nitric oxide formation in patients with acute infectious diseases. , 1999, Scandinavian journal of infectious diseases.

[35]  J. Vincent.  Cardiovascular alterations in septic shock. , 1998, The Journal of antimicrobial chemotherapy.

[36]  G. Garcı́a-Cardeña,et al.  Bacterial infection induces nitric oxide synthase in human neutrophils. , 1997, The Journal of clinical investigation.

[37]  J. Parratt.  Nitric Oxide and Cardiovascular Dysfunction in Sepsis and Endotoxaemia: An Introduction and an Overview , 1995 .

[38]  H. Ischiropoulos,et al.  Oxidative chemistry of peroxynitrite. , 1994, Methods in enzymology.

[39]  S. Padmaja,et al.  The reaction of no with superoxide. , 1993, Free radical research communications.