Bioassay of endothelium-derived relaxing factor(s): inactivation by catecholamines

1985 ◽  
Vol 249 (1) ◽  
pp. H95-H101 ◽  
Author(s):  
G. M. Rubanyi ◽  
R. R. Lorenz ◽  
P. M. Vanhoutte
Keyword(s):  
Endothelial Cells ◽  
Femoral Artery ◽  
Physiological Salt Solution ◽  
Second Phase ◽  
Partial Recovery ◽  
Rapid Phase ◽  
Relaxing Factor ◽  
Prostaglandin F2 Alpha ◽  
Bioassay Technique ◽  
Endothelium Derived Relaxing Factor

A bioassay technique was developed to analyze the effect of vasoactive substance(s) released from endothelial cells. Canine femoral arteries with or without endothelium were perfused with physiological salt solution at 37 degrees C. The perfusate was bioassayed with a ring of coronary artery without endothelium. A substance(s) released by the endothelial cells under basal conditions caused relaxation of unstimulated coronary arteries or relaxation of those contracted with prostaglandin F2 alpha. The release of the relaxing substance(s) was augmented by acetylcholine. The relaxation induced by acetylcholine was biphasic: an initial rapid phase followed by a partial recovery and a slowly developing prolonged relaxation; the half-life of the substance(s) causing the initial phase averaged 6.3 s. Norepinephrine, epinephrine, and ascorbic acid, given downstream of the femoral artery, reversibly prevented the second phase but only attenuated the initial relaxation. These observations indicate that an endothelium-derived relaxing substance(s) is released into the lumen of the femoral artery under basal conditions and during stimulation with acetylcholine. Catecholamines can inactivate the relaxing substance(s) but do not prevent either its production by endothelial cells or its action on vascular smooth muscle.

Canine arteries release two different endothelium-derived relaxing factors

1989 ◽  
Vol 257 (1) ◽  
pp. H330-H333 ◽  
Author(s):  
U. Hoeffner ◽  
M. Feletou ◽  
N. A. Flavahan ◽  
P. M. Vanhoutte
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Coronary Artery ◽  
Vascular Smooth Muscle ◽  
Coronary Arteries ◽  
Relaxing Factor ◽  
Prostaglandin F2 Alpha ◽  
Donor Artery ◽  
Canine Coronary Artery ◽  
Endothelium Derived Relaxing Factor

Experiments were designed to analyze the effects of ouabain on the response of vascular smooth muscle to endothelium-derived relaxing factors released under basal conditions and on stimulation with acetylcholine or bradykinin. Bioassay rings of canine coronary artery (without endothelium) were superfused with perfusate from canine left circumflex coronary arteries with endothelium (donor arteries). During contractions of the bioassay ring evoked by prostaglandin F2 alpha, the relaxations caused by endothelium-derived relaxing factor(s), released under basal conditions or on exposure of the endothelial cells of the donor artery to maximally effective concentrations of acetylcholine, were reduced by incubation of the bioassay ring with ouabain. However, the relaxations evoked by infusion of bradykinin were not altered by incubation of the bioassay rings with ouabain. These experiments demonstrate the release of two endothelium-derived relaxing factors that can be distinguished using ouabain.

Comparison of the release of vasoactive factors from venous and arterial bovine cultured endothelial cells

1992 ◽  
Vol 70 (5) ◽  
pp. 687-694 ◽  
Author(s):  
Pedro D'Orleans-Juste ◽  
Jane A. Mitchell ◽  
Elizabeth G. Wood ◽  
Markus Hecker ◽  
John R. Vane
Keyword(s):  
Endothelial Cells ◽  
Vena Cava ◽  
Krebs Solution ◽  
Venous Tone ◽  
Relaxing Factor ◽  
Cultured Endothelial Cells ◽  
Vasoactive Factors ◽  
Bioassay Technique ◽  
Endothelium Derived Relaxing Factor ◽  
Dose Dependent

The release of endothelium-derived relaxing factor (EDRF), prostacyclin (PGI2), and endothelin-1 (ET-1) was measured from endothelial cells (EC) cultured from either bovine vena cava (BVCEC) or bovine aorta (BAEC). EDRF release was determined by using the superfusion bioassay technique, whereas ET-1 and PGI2 were measured by specific radioimmunoassays. Bradykinin (BK) (0.05–30 pmol) given through columns of venous or arterial EC induced a dose-dependent release of EDRF. BK (0.05 pmol) evoked a release of EDRF from venous EC that was similar to the effect of a dose of 1 pmol from arterial EC. As with BAEC, infusions of NG-monomethyl-L-arginine (30 μM) caused an inhibition of EDRF release from BVCEC that was partially reversed by coinfusions of L-arginine (L-Arg; 100 μM). BK also induced a dose-dependent release of PGI2 from BVCEC. BVCEC and BAEC produced PGI2 in equivalent amounts when arachidonic acid (9.2 and 32 pmol) was added to the Krebs' solution perfusing the cells. BVEC and BAEC released detectable amounts of ET-1 (0.4 ± 0.1 and 0.9 ± 0.3 ng/mL, respectively), over a 4-h period, and the release of ET-1 was increased approximately twofold by coincubations with thrombin (0.05–1 U/mL). These findings demonstrate that venous EC have a similar capacity to arterial EC to release vasoactive factors, thus supporting the hypothesis that veins have a functional endothelium that may modulate venous tone and platelet function.Key words: cultured endothelial cells, vein, artery, endothelium-derived relaxing factor, prostacyclin, endothelin.

Prostaglandin F2 alpha-induced endothelium-dependent relaxation in isolated monkey cerebral arteries

1991 ◽  
Vol 260 (5) ◽  
pp. H1538-H1543 ◽  
Author(s):  
Y. Kawai ◽  
T. Ohhashi
Keyword(s):  
Endothelial Cells ◽  
Cerebral Arteries ◽  
Relaxing Factor ◽  
Prostaglandin F2 Alpha ◽  
Low Concentrations ◽  
Endothelium Derived Relaxing Factor ◽  
Dose Dependent ◽  
Endothelium Dependent Relaxation

Effects of prostaglandin F2 alpha (PGF2 alpha) on isolated monkey and dog cerebral arteries were investigated to reevaluate PGF2 alpha's possible action on the endothelium. Low concentrations of PGF2 alpha ranging from 10(-11) to 10(-8) M produced a dose-dependent relaxation in the monkey arteries. PGF2 alpha (10(-7) M) produced a transient contraction followed by a small relaxation, whereas higher concentrations (greater than 10(-6) M) of PGF2 alpha induced only contractions. The PGF2 alpha-induced relaxation was not observed in the canine cerebral arteries. The PGF2 alpha-induced relaxation of the monkey cerebral arteries was not affected by treatment with 10(-7) M propranolol, 10(-7) M atropine, or 10(-6) M cimetidine. In monkey cerebral arteries without endothelium, PGF2 alpha in concentrations ranging from 10(-11) to 10(-6) M caused no relaxation. Treatment with 5 X 10(-5) M aspirin, 3 X 10(-5) M NG-monomethyl-L-arginine, and 10(-5) M oxyhemoglobin significantly suppressed the PGF2 alpha-induced relaxation. These results suggest that low concentrations of PGF2 alpha may produce an endothelium-dependent relaxation in monkey cerebral arteries and that the relaxation may be mediated by release of both endogenous vasodilative prostaglandins and endothelium-derived relaxing factor from endothelial cells.

scholarly journals Superoxide anions and hyperoxia inactivate endothelium-derived relaxing factor

1986 ◽  
Vol 250 (5) ◽  
pp. H822-H827 ◽  
Author(s):  
G. M. Rubanyi ◽  
P. M. Vanhoutte
Keyword(s):  
Endothelial Cells ◽  
Superoxide Dismutase ◽  
Biological Activity ◽  
Free Radicals ◽  
Protective Effect ◽  
Femoral Artery ◽  
Superoxide Anions ◽  
Relaxing Factor ◽  
Oxygen Derived Free Radicals ◽  
Endothelium Derived Relaxing Factor

Experiments were designed to determine the effects of oxygen-derived free radicals on the production and biological activity of endothelium-derived relaxing factor or factors released by acetylcholine. Rings of canine coronary arteries without endothelium (bioassay rings) were superfused with solution passing through a canine femoral artery with endothelium. Superoxide dismutase caused maximal relaxation of the bioassay ring when infused upstream, but not downstream, of the femoral artery; this effect of superoxide dismutase was inhibited by catalase. Infusion of acetylcholine relaxed the bioassay rings because it released a labile relaxing factor (or factors) from the endothelium. When infused below the femoral artery, superoxide dismutase and, to a lesser extent, catalase augmented the relaxations to acetylcholine. Superoxide dismutase, but not catalase, doubled the half-life of the endothelium-derived relaxing factor(s). This protective effect of the enzyme was augmented fivefold by lowering the oxygen content of the perfusate from 95 to 10%. These data demonstrate that: superoxide anions inactivate the relaxing factor(s) released by acetylcholine from endothelial cells and hyperoxia favors the inactivation of endothelium-derived relaxing factor(s).

Acute compensation to abrupt occlusion of rat femoral artery is prevented by NO synthase inhibitors

1994 ◽  
Vol 267 (6) ◽  
pp. H2523-H2530 ◽  
Author(s):  
J. L. Unthank ◽  
J. C. Nixon ◽  
M. C. Dalsing
Keyword(s):  
Femoral Artery ◽  
Arterial Occlusion ◽  
Artery Occlusion ◽  
No Synthase ◽  
Artery Blood Flow ◽  
Relaxing Factor ◽  
Femoral Artery Occlusion ◽  
Before And After ◽  
Endothelium Derived Relaxing Factor ◽  
Oxide Synthase

The hemodynamic significance of endothelium-derived relaxing factor (EDRF)-mediated mechanisms in vascular responses to abrupt rat femoral artery occlusion was investigated. Temporary arterial occlusion was produced before and after inhibition of nitric oxide synthase by N omega-nitro-L-arginine methyl ester (L-NAME) or NG-monomethyl-L-arginine (L-NMMA). Iliac artery blood flow and arterial pressures proximal and distal to the occlusion were measured. Normal vascular compensation included a return of resistance to preocclusion levels and a rise in distal pressure to a plateau within 5 min postocclusion. After treatment with L-NAME and L-NMMA, postocclusion resistance remained elevated by 53 and 36%, respectively. Collateral dilation after occlusion, as indicated by the rise in distal pressure, was prevented by L-NAME but not L-NMMA. Increases in adrenergic tone and mean arterial pressure by phenylephrine did not prevent compensation, suggesting the effects of L-NAME and L-NMMA did not result from elevated sympathetic activation or pressure. The results are consistent with the hypothesis that the stimulated release of endothelium-derived relaxing factor mediates the acute vascular compensation to abrupt arterial occlusion.

scholarly journals Inhibition by l-glutamine of the release of endothelium-derived relaxing factor from cultured endothelial cells

1990 ◽  
Vol 101 (2) ◽  
pp. 237-239 ◽  
Author(s):  
Markus Hecker ◽  
Jane A. Mitchell ◽  
Tomasz A. Swierkosz ◽  
William C. Sessa ◽  
John R. Vane
Keyword(s):  
Endothelial Cells ◽  
Relaxing Factor ◽  
Cultured Endothelial Cells ◽  
Endothelium Derived Relaxing Factor

Endothelium and mechanical responses of isolated monkey pulmonary veins to histamine

1990 ◽  
Vol 259 (4) ◽  
pp. H1032-H1037 ◽  
Author(s):  
T. Matsuki ◽  
T. Ohhashi
Keyword(s):  
Pulmonary Veins ◽  
Dependent Manner ◽  
High Concentration ◽  
Concentration Dependent Manner ◽  
Mechanical Responses ◽  
Relaxing Factor ◽  
Prostaglandin F2 Alpha ◽  
H2 Receptors ◽  
Endothelium Derived Relaxing Factor ◽  
Stimulation Of

Ring strips of monkey pulmonary veins precontracted with a high concentration of prostaglandin F2 alpha (PGF2 alpha) relaxed in a concentration-dependent manner in response to histamine. Treatment with mepyramine and/or famotidine attenuated the relaxation. 2-Pyridylethylamine (2PEA) and dimaprit caused relaxations in the precontracted preparations, which were inhibited by pretreatment with mepyramine and famotidine, respectively. Removal of endothelium reversed the histamine- and 2PEA-induced relaxations to dose-related contractions. On the other hand, the removal had no effect on the dimaprit-induced relaxations, which were significantly reduced by pretreatment with famotidine. Histamine-induced relaxations in the precontracted strips with endothelium in the presence and absence of famotidine were suppressed or abolished by treatment with methylene blue or hemoglobin but were unaffected by aspirin. It may be concluded that histamine-induced relaxation in monkey pulmonary veins precontracted with PGF2 alpha is mediated by H2-receptors in smooth muscle and H1-receptors in endothelium. Also, stimulation of the endothelial H1-receptors liberates an endothelium-derived relaxing factor.

Enhanced release of endothelium-derived factor(s) by chronic increases in blood flow

1988 ◽  
Vol 255 (3) ◽  
pp. H446-H451 ◽  
Author(s):  
V. M. Miller ◽  
P. M. Vanhoutte
Keyword(s):  
Blood Flow ◽  
Smooth Muscle ◽  
Arteriovenous Fistula ◽  
Muscarinic Receptors ◽  
Femoral Artery ◽  
Response Curves ◽  
Femoral Arteries ◽  
Relaxing Factor ◽  
Bioassay System ◽  
Endothelium Derived Relaxing Factor

Chronic increases in blood flow caused by an arteriovenous fistula augment endothelium-dependent relaxations to acetylcholine. To determine whether endothelial muscarinic receptors are altered, concentration-response curves to acetylcholine were obtained in the presence of pirenzepine in fistula- and sham-operated canine femoral arteries. Pirenzepine inhibited the response to acetylcholine in both arteries. The pA2 (log Kb) for the antagonist was the same. A bioassay system was used to assess release of endothelium-derived relaxing factor. Rings of femoral artery (without endothelium) from unoperated dogs relaxed more when superfused with perfusate derived from endothelium of fistula-operated arteries during acetylcholine stimulation. Rings without endothelium of sham- and fistula-operated arteries relaxed to the same extent when superfused with perfusate derived from the endothelium of unoperated femoral arteries. These results suggest that augmented relaxations to acetylcholine in canine arteries where blood flow is chronically elevated do not result from changes in the subtype of endothelial muscarinic receptors or in the sensitivity of the underlying smooth muscle to endothelium-derived relaxing factor(s). They are likely due to increased release of endothelium-derived relaxing factor(s) on muscarinic activation.

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