Ductus arteriosus: involvement of a sarcolemmal cytochrome P-450 in O2 constriction?

1989 ◽  
Vol 67 (11) ◽  
pp. 1448-1450 ◽  
Author(s):  
Flavio Coceani ◽  
Julie Wright ◽  
Carole Breen
Keyword(s):  
Carbon Monoxide ◽  
Ductus Arteriosus ◽  
Signal Transducer ◽  
Mixture Ratio ◽  
Skinned Muscle ◽  
Sequence Of Events ◽  
Membrane Bound ◽  
Cytochrome P 450 ◽  
Constrictor Response ◽  
Insight Into

Our previous studies implicate a cytochrome P-450-based mechanism in the constrictor response of the ductus arteriosus to oxygen. The present experiments were conducted on saponin-skinned strips of ductal muscle from mature fetal lambs to determine the location, sarcolemmal versus intracellular, of this cytochrome and to obtain a better insight into the sequence of events underlying the action of oxygen. Skinned preparations contracted to free Ca2+ over the range between 0.1 and 5–10 μM (pCa 7 to 5). In contrast, oxygen (Po2, 608–690 Torr; 1 Torr = 133.3 Pa) had no significant effect, both in the absence and presence of 10 μM calcium. Carbon monoxide, tested as pure CO or a CO–O2 mixture (ratio 0.28), did not relax preparations maximally contracted with calcium. These findings indicate that oxygen exerts its effect on the plasma membrane of ductus muscle cells and that a membrane-bound cytochrome P-450 mechanism likely functions as the signal transducer for oxygen in the formation of a constrictor agent.Key words: ductus arteriosus closure, chemically skinned muscle, second messenger.

scholarly journals EDHF function in the ductus arteriosus: evidence against involvement of epoxyeicosatrienoic acids and 12S-hydroxyeicosatetraenoic acid

2009 ◽  
Vol 297 (6) ◽  
pp. H2161-H2168 ◽  
Author(s):  
Barbara Baragatti ◽  
Michal Laniado Schwartzman ◽  
Debora Angeloni ◽  
Francesca Scebba ◽  
Enrica Ciofini ◽  
...  
Keyword(s):  
Nitric Oxide ◽  
Carbon Monoxide ◽  
Arachidonic Acid ◽  
Ductus Arteriosus ◽  
Epoxyeicosatrienoic Acids ◽  
Spectrometric Analysis ◽  
Hydroxyeicosatetraenoic Acid ◽  
Acid Product ◽  
Acid Metabolites ◽  
Cytochrome P 450

We have previously shown (Ref. 2 ) that endothelium-derived hyperpolarizing factor (EDHF) becomes functional in the fetal ductus arteriosus on removal of nitric oxide and carbon monoxide. From this, it was proposed that EDHF originates from a cytochrome P-450 (CYP450)-catalyzed reaction being inhibited by the two agents. Here, we have examined in the mouse ductus whether EDHF can be identified as an arachidonic acid product of a CYP450 epoxygenase and allied pathways. We did not detect transcripts of the mouse CYP2C subfamily in vessel, while CYP2J subfamily transcripts were expressed with CYP2J6 and CYP2J9. These CYP2J hemoproteins were also detected in the ductus by immunofluorescence microscopy, being colocalized with the endoplasmic reticulum in both endothelial and muscle cells. Distinct CYP450 transcripts were also detected and were responsible for ω-hydroxylation (CYP4A31) and 12R-hydroxylation (CYP4B1). Mass spectrometric analysis showed formation of epoxyeicosatrienoic acids (EETs) in the intact ductus, with 11,12- and 14,15-EETs being more prominent than 5,6- and 8,9-EETs. However, their yield did not increase with nitric oxide/carbon monoxide suppression, nor did it abate with endothelium removal. No evidence was obtained for formation of 12R-hydroxyeicosatrienoic acid and ω-hydroxylation products. 2S-hydroxyeicosatetraenoic acid was instead detected, and, contrary to data implicating this compound as an alternative EDHF, its suppression with baicalein did not modify the EDHF-mediated relaxation to bradykinin. We conclude that none of the more common CYP450-linked arachidonic acid metabolites appears to qualify as EDHF in mouse ductus. We speculate that some novel eicosanoid or a totally unrelated compound requiring CYP450 for its synthesis accounts for EDHF in this vessel.

Oxygenation of 18-hydroxycorticosterone as the final reaction for aldosterone biosynthesis

1984 ◽  
Vol 107 (3) ◽  
pp. 395-400 ◽  
Author(s):  
Itaru Kojima ◽  
Etsuro Ogata ◽  
Hiroshi Inano ◽  
Bun-ichi Tamaoki
Keyword(s):  
Carbon Monoxide ◽  
Hydroxysteroid Dehydrogenase ◽  
Dependent Manner ◽  
In Vitro Production ◽  
Mitochondrial Preparation ◽  
Final Reaction ◽  
Vitro Production ◽  
Dose Dependent ◽  
Cytochrome P 450

Abstract. Incubation of 18-hydroxycorticosterone with the sonicated mitochondrial preparation of bovine adrenal glomerulosa tissue leads to the production of aldosterone, as measured by radioimmunoassay. The in vitro production of aldosterone from 18-hydroxycorticosterone requires both molecular oxygen and NADPH, and is inhibited by carbon monoxide. Cytochrome P-450 inhibitors such as metyrapone, SU 8000. SU 10603, SKF 525A, amphenone B and spironolactone decrease the biosynthesis of aldosterone from 18-hydroxycorticosterone. These results support the conclusion that the final reaction in aldosterone synthesis from 18-hydroxycorticosterone is catalyzed by an oxygenase, but not by 18-hydroxysteroid dehydrogenase. By the same preparation, the production of [3H]aldosterone but not [3H]18-hydroxycorticosterone from [1,2-3H ]corticosterone is decreased in a dose-dependent manner by addition of non-radioactive 18-hydroxycorticosterone.

An atomic-level insight into the basic mechanism responsible for the enhancement of the catalytic oxidation of carbon monoxide on a Cu/CeO2 surface

2017 ◽  
Vol 19 (5) ◽  
pp. 3498-3505 ◽  
Author(s):  
Kenichi Koizumi ◽  
Katsuyuki Nobusada ◽  
Mauro Boero
Keyword(s):  
Carbon Monoxide ◽  
Reaction Mechanism ◽  
Catalytic Oxidation ◽  
Morphological Changes ◽  
Basic Mechanism ◽  
Atomic Level ◽  
Insight Into ◽  
Oxidation Of Carbon Monoxide

Reaction mechanism of CO molecules onto a Cu/CeO2 surface and morphological changes.

scholarly journals Genome Annotation Provides Insight into Carbon Monoxide and Hydrogen Metabolism in Rubrivivax gelatinosus

PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e114551 ◽  
Author(s):  
Karen Wawrousek ◽  
Scott Noble ◽  
Jonas Korlach ◽  
Jin Chen ◽  
Carrie Eckert ◽  
...  
Keyword(s):  
Carbon Monoxide ◽  
Genome Annotation ◽  
Hydrogen Metabolism ◽  
Rubrivivax Gelatinosus ◽  
Insight Into

SOME CHEMICAL PROPERTIES OF CYTOCHROME P-450 AND ITS CARBON MONOXIDE COMPOUND (P-450.CO)

1970 ◽  
Vol 174 (1 Biological Ef) ◽  
pp. 205-217 ◽  
Author(s):  
David Y. Cooper ◽  
Heinz Schleyer ◽  
Dr. rer. Nat ◽  
Otto Rosenthal
Keyword(s):  
Carbon Monoxide ◽  
Chemical Properties ◽  
Cytochrome P 450

scholarly journals Inhaled carbon monoxide does not cause pulmonary vasodilation in the late-gestation fetal lamb

2000 ◽  
Vol 278 (4) ◽  
pp. L779-L784 ◽  
Author(s):  
Theresa R. Grover ◽  
Robyn L. Rairigh ◽  
Jeanne P. Zenge ◽  
Steven H. Abman ◽  
John P. Kinsella
Keyword(s):  
Carbon Monoxide ◽  
Blood Flow ◽  
Pulmonary Artery ◽  
Vascular Tone ◽  
Ductus Arteriosus ◽  
Protoporphyrin Ix ◽  
Left Lung ◽  
Late Gestation ◽  
Zinc Protoporphyrin ◽  
Pulmonary Vasodilation

As observed with nitric oxide (NO), carbon monoxide (CO) binds and may activate soluble guanylate cyclase and increase cGMP levels in smooth muscle cells in vitro. Because inhaled NO (INO) causes potent and sustained pulmonary vasodilation, we hypothesized that inhaled CO (ICO) may have similar effects on the perinatal lung. To determine whether ICOcan lower pulmonary vascular resistance (PVR) during the perinatal period, we studied the effects of ICOon late-gestation fetal lambs. Catheters were placed in the main pulmonary artery, left pulmonary artery (LPA), aorta, and left atrium to measure pressure. An ultrasonic flow transducer was placed on the LPA to measure blood flow to the left lung. After baseline measurements, fetal lambs were mechanically ventilated with a hypoxic gas mixture (inspired O2fraction < 0.10) to maintain a constant fetal arterial [Formula: see text]. After 60 min (baseline), the lambs were treated with ICO[5–2,500 parts/million (ppm)]. Comparisons were made with INO(5 and 20 ppm) and combined INO(5 ppm) and ICO(100 and 2,500 ppm). We found that ICOdid not alter left lung blood flow or PVR at any of the study doses. In contrast, low-dose INOdecreased PVR by 47% ( P < 0.005). The combination of INOand ICOdid not enhance the vasodilator response to INO. To determine whether endogenous CO contributes to vascular tone in the fetal lung, zinc protoporphyrin IX, an inhibitor of heme oxygenase, was infused into the LPA in three lambs. Zinc protoporphyrin IX had no effect on baseline PVR, aortic pressure, or the pressure gradient across the ductus arteriosus. We conclude that ICOdoes not cause vasodilation in the near-term ovine transitional circulation, and endogenous CO does not contribute significantly to baseline pulmonary vascular tone or ductus arteriosus tone in the late-gestation ovine fetus.

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