Open AccessThe Effects of Diaspirin Cross-Linked Hemoglobin on the Tone of Human Saphenous Vein
Author(s) -
Mark Forrest,
Adrian H. Chester,
David Royston
Publication year - 2001
Publication title -
anesthesia and analgesia/anesthesia and analgesia
Language(s) - English
Resource type - Journals
eISSN - 1526-7598
pISSN - 0003-2999
DOI - 10.1097/00000539-200102000-00007
Subject(s) - dilator , sodium nitroprusside , vasoconstriction , medicine , vasodilation , nitric oxide , anesthesia , hemoglobin , vein , sildenafil , cardiology
Diaspirin cross-linked hemoglobin (DCL-Hb), when infused into animals, causes vasoconstriction thought to be caused by nitric oxide (NO) binding by the hemoglobin molecule. The purpose of this study was to ascertain whether DCL-Hb causes vasoconstriction in human saphenous vein taken from patients undergoing myocardial revascularization and whether NO scavenging is the mechanism. The direct effect of DCL-Hb on saphenous vein tone was tested by adding increasing concentrations (10(-8) to 10(-5)M) of the drug. In an additional series of experiments, the influence of DCL-Hb on the dilator response to endothelial dependent and independent vasodilators was tested. This was achieved by attempting either to reverse the effects of acetylcholine, sodium nitroprusside, or S-nitrosylglutathione with prior incubation with DCL-Hb or to inhibit the dilator response in vessels preconstricted with 10(-6)M norepinephrine. There was no effect of DCL-Hb alone on saphenous vein tone. DCL-Hb significantly reduced vasodilatation with all vasodilators (P < 0.05). After maximal relaxation with sodium nitroprusside and s-nitrosylglutathione, there was significant vasoconstriction with DCL-Hb at concentrations larger than 10(-6)M, (P < 0.05). The authors conclude that DCL-Hb does not constrict human saphenous vein but can affect vessel tone by reversal of the effect of endogenously or exogenously released NO.