Unknown

Dataset Information

0

Leukotriene B4 synthesis and metabolism by neutrophils and granule-free cytoplasts.


ABSTRACT: Leukotriene B4 [LTB4, (5S,12R)-hydroxyeicosa-6,14-cis-8,10-trans-tetraenoic acid], a potent mediator of inflammation, is released from neutrophils by agonists that provoke degranulation of the cell. To examine whether degranulation is a necessary requirement for synthesis and metabolism of LTB4 (or of other arachidonate metabolites), we prepared neutrophil-derived cytoplasts (neutroplasts), organelle-depleted vesicles of cytoplasm surrounded by the plasma membrane. In the presence of extracellular Ca2+ with or without exogenous arachidonic acid (150 microM), neutroplasts were exposed to the Ca2+ ionophore A23187 (10 microM) and the resultant lipoxygenation products of arachidonate were determined. Neutrophils metabolize arachidonic acid to 5-HETE greater than 15-HETE greater than LTB4 greater than all-trans-LTB4 isomers. Neutroplast products of arachidonate lipoxygenation were 15-HETE greater than 5-HETE greater than LTB4 greater than all-trans-LTB4 isomers. Neutroplasts, like neutrophils, were capable of converting LTB4 into its 20-hydroxy and 20-carboxy metabolites. Finally, neutroplasts could utilize intrinsic arachidonate, since the neutroplasts synthesized LTB4 (30 pmol/mg of protein) in the absence of added arachidonic acid. The data demonstrate that neutrophil degranulation is not required for synthesis or metabolism of LTB4 by neutrophils.

SUBMITTER: Haines KA 

PROVIDER: S-EPMC1153066 | biostudies-other | 1986 Jan

REPOSITORIES: biostudies-other

Similar Datasets

| S-EPMC1147523 | biostudies-other
| S-EPMC1135652 | biostudies-other
| S-EPMC1151577 | biostudies-other
| S-EPMC3170431 | biostudies-literature
| S-EPMC6444630 | biostudies-literature
2011-09-21 | GSE24869 | GEO
2003-04-14 | GSE390 | GEO
| S-EPMC2118292 | biostudies-literature
| S-EPMC4076593 | biostudies-literature
2011-09-20 | E-GEOD-24869 | biostudies-arrayexpress