Respiratory burst mechanisms

It is well-established that a major response to septic stimuh in general is the activation (primarily by cytokines and bacterial products, conditions that as described above also can induce NO synthesis) of phagocytic cells (neutrophils, macrophages) to produce ROS, through the respiratory burst mechanism this is a major immune mechanism for combating infectious agents but also can be damaging to the host. 

Suematsu, M., Suzuki, M., Miura, S., Miura, S., Suzuki, K., Hibi, T., Watanabe, M. and Tsuchiya (1987b). Sulfasalazine and its metabolites attenuate respiratory burst of leukocytes -a possible mechanism of anti-inflammatory effects. J. Clin. Lab. Immunol. 23, 31-33. 

In addition to the well-characterized role of iron in catalysing redox interactions, other metallic contaminants, for example, nickel, may also contribute. In vivo toxicity studies have demonstrated the capacity of nickel particulate compounds to induce tumours following intraperitoneal injection (Pott etal., 1987). Such activity is proportional to their phagocytic uptake, and to the associated respiratory burst and generation of PMN-derived reactive oxygen metabolites (ROMs), a proposed pathogenic mechanism (Evans et al., 1992a). 

Wiik, P. (1989). Vasoactive intestinal peptide inhibits the respiratory burst in human monocytes by a cyclic AMP-mediated mechanism. Regul. Pept. 25, 187-197. 

From the flood of results obtained by measurements of the different manifestations of the respiratory burst—O2 consumption Oi, H2O2, and OH production and chemiluminescence—some general features can be outlined which are common to all these events, suggesting that they could all depend on a single initial triggering mechanism. 

Gomisin C has an inhibitory effect on the respiratory burst of rat neutrophils in vitro [243], The mechanism of action may be mediated partly by the suppression of NADPH oxidase and partly by the decrease in cytosolic Ca2+ released from an agonist-sensitive intracellular store. In fact, gomisin C attenuated the activity of TPA-activated neutrophil particulate NADPH oxidase in a concentration-dependent manner and reduced the increase in cytosolic free Ca2+ in neutrophils stimulated by fMLP in presence or absence of ethylenediaminetetraacetic acid (EDTA). In addition, this study suggests that the gomisin C mechanism is not mediated by changes in cellular cAMP or in inositol phosphates, or by scavenging... 

---