TNF-alpha alters nitric oxide- and endothelium-derived hyperpolarizing factor-mediated vasodilatation in human omental arteries.
OBJECTIVE
To investigate the effect of TNF-alpha on the endothelial function of human systemic arteries.


METHODS
Omental arteries were obtained from healthy pregnant women undergoing Cesarean section and examined using isometric wire myography.


RESULTS
Incubation with TNF-alpha (1nM) alone did not alter bradykinin-mediated endothelium-dependent relaxation of arteries. However, TNF-alpha did attenuate nitric oxide- (NO) and prostacyclin-independent endothelial-mediated relaxation. Similarly, in vessels constricted with a high potassium solution (60 mM), which inhibits vasodilatation via endothelial-derived hyperpolarising factor (EDHF), TNF-alpha incubation also attenuated bradykinin-induced vasodilatation.


CONCLUSIONS
The vasorelaxant capacity of human systemic arteries is compromised by TNF-alpha incubation in the presence of NO/prostacyclin or EDHF-blockade.
Gillham
J C
JC
Maternal and Fetal Health Research Centre, Division of Human Development, St Mary's Hospital, Manchester, UK.
Myers
J E
JE
Baker
P N
PN
Taggart
M J
MJ
D000328:Adult; D001158:Arteries / Q000502:physiology*; D001685:Biological Factors / Q000502:physiology*; D001920:Bradykinin / Q000502:physiology; D004730:Endothelium, Vascular / Q000502:physiology*; D011464:Epoprostenol / Q000502:physiology; D005260:Female; D006801:Humans; D009569:Nitric Oxide / Q000502:physiology*; D009852:Omentum / Q000098:blood supply; D014409:Tumor Necrosis Factor-alpha / Q000494:pharmacology*; D014664:Vasodilation / Q000502:physiology*
D001685:Biological Factors; D014409:Tumor Necrosis Factor-alpha; C067410:endothelium-dependent hyperpolarization factor; D009569:Nitric Oxide; D011464:Epoprostenol; D001920:Bradykinin