Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0027947 (neutropenia)
 17,527 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

The ability of various leukotrienes, platelet-activating factor and N-formyl-methyl-leucyl-phenylalanine to augment colonic damage induced by 30% ethanol was investigated in the rat. Each of the mediators was tested at a dose of 2 nmol, administered intracolonically in the ethanol vehicle. When colonic damage was assessed 72 hr later, only leukotriene B4 significantly augmented damage compared to the controls. The incidence of ulcers increased from 35% in the control group to 90% in the group receiving leukotriene B4. Leukotriene B4 administration also resulted in significant increases in colonic myeloperoxidase activity and colonic leukotriene B4 synthesis. To assess the possible contribution of infiltrating neutrophils to the increase in colonic leukotriene B4 synthesis that accompanies colonic inflammation, colitis was induced in normal and neutropenic rats by intracolonic administration of trinitrobenzene sulfonic acid. Neutropenia was achieved by treatment with an antineutrophil serum. In the neutropenic animals killed 4 hr after induction of colitis significant changes in leukotriene B4 synthesis were not observed, whereas a fourfold increase was observed in the controls. From these studies we conclude the following: (1) leukotriene B4, at a dose of 2 nmol, can significantly potentiate the colonic ulceration induced by 30% ethanol; (2) this action of leukotriene B4 is not shared by the same dose of the other inflammatory mediators tested; and (3) infiltrating neutrophils are the major source of colonic leukotriene B4 synthesis in a rat model of colitis.
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PMID:Leukotriene B4 potentiates colonic ulceration in the rat. 215 82

Leukotriene B4 (LTB4 isomer III), which promotes the movement and aggregation of leucocytes in vitro also stimulates the chemo-attraction of leucocytes and their adherence to vascular endothelium in vivo. These effects were observed directly in the hamster cheek pouch preparation and on histological examination of sections from the rabbit mesentery. Intravenous injection of LTB4 (isomer III) into the rabbit resulted in a profound but transient neutropenia. Intradermal injection of LTB4 (isomer III) in the rabbit produced a rapid accumulation of neutrophils and this effect was also observed in skin chambers applied over abrasions on the rabbit back or the human forearm.
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PMID:Leukotriene B4: an inflammatory mediator in vivo. 627 Jul 42

Leukotriene B4 (LTB4) is a 5, 12-dihydroxy derivative of arachidonic acid generated by a variety of inflammatory cells via the lipoxygenase enzyme system. In vitro leukotriene B4 is a potent chemotactic and aggregatory agent; enhances neutrophil complement receptors; stimulates membrane calcium changes and causes contraction of lung parenchyma. In vivo LTB4 is a potent stimulator of vascular permeability in rats, rabbits, guinea-pigs and man particularly in the presence of a vasodilator such as PGE2. LTB4 causes a profound transient neutropenia and massive accumulation of neutrophils when injected into the dermis (rabbit and man), skin chambers (rabbit and man) or body cavities (guinea-pig, rat).
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PMID:Leukotriene B4: an inflammatory mediator with vascular actions in vivo. 629 13