Formyl methionyl-leucyl phenylalanine fMLP

Stenson, W.F., Mehta, J. and Spilbeig, I. (1984). Sulfiasalazine inhibition of binding of N-formyl-methionyl-leucyl-phenylalanine (FMLP) to its receptor on human neutrophils. Biochem. Pharm. 33, 407-412. 

A-formyl-methionyl-leucyl-phenylalanine (FMLP) (Sigma) FMLP is prepared as a stock solution of 1 mM in ethanol and stored at -20°C. 

Studies of Lsc in neutrophils also suggest that localization may play a role in activation of Rho (Francis et al., 2006). Immunostaining showed that Lsc was largely distributed uniformly on the plasma membrane. After 5 min of stimulation with W-formyl-methionyl-leucyl-phenylalanine (fMLP), the Lsc became enriched in the leading and trailing edges of the cells, sites of active cytoskeletal reorganization in these stimulated cells. While simple translocation to the plasma membranes does not appear to be a viable mechanism for activation in this case, localization within the membrane to direct activity to specific sites is indicated. 

Maggi CA, Santicioli P, Del Bianco E, Giuliani S (1992) Local motor responses to bradykinin and bacterial chemotactic peptide formyl-methionyl-leucyl-phenylalanine (FMLP) in the guinea pig isolated renal pelvis and ureter. J Urol 14 1944-1950... 

Figure 9.9 Microradiograph of neutrophils isolated from human peripheral hlood and incubated with H-DG for 1 h. (a) Control unprimed cells (h) tumor necrosis factor a (TNF-a)-primed and Af-formyl-methionyl-leucyl-phenylalanine (fMLP)-stimulated cells (c) unprimed cells stimulated with fMLP (d) TNF-a-primed hut unstimulated cells.

There was no evidence from cell-free assay systems that carvedilol is a scavenger for 02 or NO (Asbrink et al. 2000). Carvedilol did not affect other reactions dependent on NO, e.g. spontaneous of formyl-methionyl-leucyl-phenylalanine-stimulated polymorphonuclear leucocyte migration or hpoxin A4-, fMLP-, or A23187-induced neutrophil cytotoxicity for human umbiUcal vein endothehal cells. Thus, these effects point to the possibility that carvedilol modulates the NADPH oxidase of polymorphonuclear leucocytes but leaves the nitric oxide synthase of phagocytes intact. Carvedilol exerted poor reactivity toward phenoxyl, alkoxyl, and per-oxyl radicals in acetonitrile solution nor did it show an appreciable antioxidant effect against either the peroxyl radical-induced oxidation of methyl Unole-... 

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