5-Lipoxygenase activity in the human pancreas.
Low levels of 5-lipoxygenase (5-LO), the first committed enzyme in the synthesis of leukotrienes (LTs), have been reported in the porcine pancreas. We have quantitated 5-LO activity in subcellular fractions of pancreas samples from three human donors. 5-LO activity was detectable in all samples, although enzyme activity was lower than in human leukocytes. 5-LO in human pancreas samples displayed highest specific activity in membrane fractions, and did not require arachidonic acid (AA) addition for activity. These unusual characteristics of pancreatic 5-LO appear to be due, at least in part, to the presence of unesterified AA in the pancreas samples. Western blot analysis demonstrated that the human pancreas contains low levels of 5-lipoxygenase-activating protein (FLAP) in addition to 5-LO.
Mancini
J A
JA
Department of Pharmacology, Merck Frosst Centre for Therapeutic Research, Quebec, Canada.
Li
C
C
Vickers
P J
PJ
D058927:5-Lipoxygenase-Activating Proteins; D001094:Arachidonate 5-Lipoxygenase / Q000032:analysis / Q000378:metabolism*; D016718:Arachidonic Acid / Q000494:pharmacology; D015153:Blotting, Western; D002352:Carrier Proteins / Q000032:analysis; D002851:Chromatography, High Pressure Liquid; D005260:Female; D006801:Humans; D017572:Leukotriene A4 / Q000378:metabolism; D007975:Leukotriene B4 / Q000378:metabolism; D015289:Leukotrienes / Q000378:metabolism; D008297:Male; D008565:Membrane Proteins / Q000032:analysis; D008875:Middle Aged; D010179:Pancreas / Q000201:enzymology* / Q000648:ultrastructure; D013347:Subcellular Fractions / Q000201:enzymology
D058927:5-Lipoxygenase-Activating Proteins; C548592:ALOX5AP protein, human; D002352:Carrier Proteins; D017572:Leukotriene A4; D015289:Leukotrienes; D008565:Membrane Proteins; D007975:Leukotriene B4; D016718:Arachidonic Acid; C025348:arachidonic acid 5-hydroperoxide; D001094:Arachidonate 5-Lipoxygenase