Pasteurella haemolytica leukotoxin enhances production of leukotriene B4 and 5-hydroxyeicosatetraenoic acid by bovine polymorphonuclear leukocytes.
The influence of the leukotoxin of Pasteurella haemolytica on the generation of arachidonic acid metabolites by bovine polymorphonuclear leukocytes (PMNs) was investigated. PMNs released 5-, 12-, and 15-hydroxyeicosatetraenoic acids (5-, 12-, and 15-HETE) and leukotriene B4 (LTB4) upon stimulation with arachidonic acid. The leukotoxin preparations dose dependently enhanced the release of the 5-lipoxygenase products 5-HETE and LTB4 in arachidonic acid-stimulated PMNs, whereas the release of 12- and 15-HETE was not affected. The enhanced release of LTB4 and 5-HETE was not due to a decreased cellular retention of the 5-lipoxygenase products. In addition, leukotoxin preparations by themselves were also able to induce LTB4 and 5-HETE production in the absence of exogenous arachidonic acid. Generation of 5-lipoxygenase products by PMNs stimulated by leukotoxin may represent an important cellular event that occurs during infections with P. haemolytica.
Henricks
P A
PA
Department of Pharmacology, Faculty of Pharmacy, University of Utrecht, The Netherlands.
Binkhorst
G J
GJ
Drijver
A A
AA
Nijkamp
F P
FP
D000818:Animals; D001427:Bacterial Toxins / Q000494:pharmacology*; D002417:Cattle; D002478:Cells, Cultured; D005098:Exotoxins / Q000494:pharmacology*; D006801:Humans; D006893:Hydroxyeicosatetraenoic Acids / Q000096:biosynthesis*; D007975:Leukotriene B4 / Q000096:biosynthesis*; D016978:Mannheimia haemolytica / Q000378:metabolism*; D009504:Neutrophils / Q000378:metabolism*; D013045:Species Specificity
D001427:Bacterial Toxins; D005098:Exotoxins; D006893:Hydroxyeicosatetraenoic Acids; C018579:leukotoxin; D007975:Leukotriene B4; C022022:5-hydroxy-6,8,11,14-eicosatetraenoic acid; C025984:15-hydroxy-5,8,11,13-eicosatetraenoic acid