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Bovine polymorphonuclear leukocytes increase sensitivity to noradrenaline in isolated mesenteric arteries.
- Source :
-
British journal of pharmacology [Br J Pharmacol] 1992 Mar; Vol. 105 (3), pp. 581-6. - Publication Year :
- 1992
-
Abstract
- 1. The effects of polymorphonuclear leukocytes (PMN) on vascular function to (-)-noradrenaline were examined in vitro. Purified bovine PMN were incubated in siliconized organ baths containing rings of bovine mesenteric arteries, after which a concentration-effect curve in response to (-)-noradrenaline was obtained. 2. PMN-derived products induced a long lasting concentration-dependent contraction of the blood vessels generating 24.4 +/- 6.8% of the maximal tension to (-)-noradrenaline at a cell concentration of 2.5 x 10(6) ml-1. The contractile response was also found in endothelium-denuded vascular rings. 3. PMN present in the organ bath caused an increase in the sensitivity of vascular rings to (-)-noradrenaline. At a cell number of 2.5 x 10(6) PMN ml-1 the pD2-value for (-)-noradrenaline was augmented 0.40 +/- 0.05 (P less than 0.001), while total contraction at the highest concentration (-)-noradrenaline was not affected. This increase in sensitivity was dependent on an intact endothelium. 4. The increase in sensitivity to (-)-noradrenaline by PMN was inhibited by superoxide dismutase, but not by catalase, dimethylthiourea, indomethacin or nordihydroguaiaretic acid. The non-stimulated bovine PMN produced oxygen radicals as measured by chemiluminescence. 5. Simultaneous incubation of PMN and (-)-noradrenaline with arterial rings induced an increase in the release of prostacyclin, measured by an elevated concentration of 6-keto-prostaglandin F1 alpha in the supernatant. 6. It is concluded that PMN can increase vascular tone directly or indirectly probably via the interaction of PMN-derived superoxide anions with endothelium-derived relaxing factor.
- Subjects :
- 6-Ketoprostaglandin F1 alpha biosynthesis
Animals
Arachidonic Acid metabolism
Arginine analogs & derivatives
Arginine pharmacology
Cattle
Free Radical Scavengers
In Vitro Techniques
Luminescent Measurements
Mesenteric Arteries drug effects
Mesenteric Arteries physiology
Muscle Contraction drug effects
Muscle, Smooth, Vascular metabolism
Muscle, Smooth, Vascular physiology
Radioimmunoassay
Thromboxane B2 biosynthesis
omega-N-Methylarginine
Muscle, Smooth, Vascular drug effects
Neutrophils physiology
Norepinephrine pharmacology
Subjects
Details
- Language :
- English
- ISSN :
- 0007-1188
- Volume :
- 105
- Issue :
- 3
- Database :
- MEDLINE
- Journal :
- British journal of pharmacology
- Publication Type :
- Academic Journal
- Accession number :
- 1628145
- Full Text :
- https://doi.org/10.1111/j.1476-5381.1992.tb09022.x