The Role of Nitric Oxide in the Control of Coronary Vascular Tone in Relation to Partial Oxygen Pressure, Perfusion Pressure, and Flow

The time profile of changes in the oxygen saturation curves of human hemoglobin in the presence of benzene was investigated. The partial oxygen pressure p50, necessary for a half saturation, decreases during the first 3.5 h of interaction of hemoglobin with benzene and did not change afterwards. The character of changes in Hill's coefficient was similar. The oxygen saturation was modeled both for hemoglobin alone and, using MWC as a model of allosteric interaction, also for hemoglobin and benzene in a computer.

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Mismatch between Tissue Partial Oxygen Pressure and Near-Infrared Spectroscopy Neuromonitoring of Tissue Respiration in Acute Brain Trauma: The Rationale for Implementing a Multimodal Monitoring Strategy

International Journal of Molecular Sciences ◽

10.3390/ijms22031122 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1122

Author(s):

Mario Forcione ◽

Mario Ganau ◽

Lara Prisco ◽

Antonio Maria Chiarelli ◽

Andrea Bellelli ◽

...

Keyword(s):

Infrared Spectroscopy ◽

Near Infrared Spectroscopy ◽

Oxygen Pressure ◽

Near Infrared ◽

Optical Signal ◽

Brain Trauma ◽

Partial Oxygen Pressure ◽

Tissue Respiration ◽

The Brain ◽

Partial Oxygen

The brain tissue partial oxygen pressure (PbtO2) and near-infrared spectroscopy (NIRS) neuromonitoring are frequently compared in the management of acute moderate and severe traumatic brain injury patients; however, the relationship between their respective output parameters flows from the complex pathogenesis of tissue respiration after brain trauma. NIRS neuromonitoring overcomes certain limitations related to the heterogeneity of the pathology across the brain that cannot be adequately addressed by local-sample invasive neuromonitoring (e.g., PbtO2 neuromonitoring, microdialysis), and it allows clinicians to assess parameters that cannot otherwise be scanned. The anatomical co-registration of an NIRS signal with axial imaging (e.g., computerized tomography scan) enhances the optical signal, which can be changed by the anatomy of the lesions and the significance of the radiological assessment. These arguments led us to conclude that rather than aiming to substitute PbtO2 with tissue saturation, multiple types of NIRS should be included via multimodal systemic- and neuro-monitoring, whose values then are incorporated into biosignatures linked to patient status and prognosis. Discussion on the abnormalities in tissue respiration due to brain trauma and how they affect the PbtO2 and NIRS neuromonitoring is given.

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Synthesis of monophase HgBa2CuO4+δ under controlled partial oxygen pressure

Physica C Superconductivity ◽

10.1016/0921-4534(95)00633-8 ◽

1995 ◽

Vol 255 (3-4) ◽

pp. 173-179 ◽

Cited By ~ 44

Author(s):

V.A. Alyoshin ◽

D.A. Mikhailova ◽

E.V. Antipov

Keyword(s):

Oxygen Pressure ◽

Partial Oxygen Pressure ◽

Partial Oxygen

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Correlation Between The Inspired Fraction Of Oxygen, Maternal Partial Oxygen Pressure, And Fetal Partial Oxygen Pressure During Cesarean Section Of Normal Pregnancies

Brazilian Journal of Anesthesiology ◽

10.1590/s0034-70942009000400007 ◽

2009 ◽

Vol 59 (4) ◽

pp. 452-460 ◽

Cited By ~ 2

Author(s):

Carlos Henrique Viana de Castro ◽

Marcos Guilherme Cunha Cruvinel ◽

Fabiano Soares Carneiro ◽

Yerkes Pereira Silva ◽

Antônio Carlos Vieira Cabral ◽

...

Keyword(s):

Cesarean Section ◽

Oxygen Pressure ◽

Partial Oxygen Pressure ◽

Partial Oxygen

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Role of PGI2 and epoxyeicosatrienoic acids in relaxation of bovine coronary arteries to arachidonic acid

AJP Heart and Circulatory Physiology ◽

10.1152/ajpheart.1993.264.2.h327 ◽

1993 ◽

Vol 264 (2) ◽

pp. H327-H335 ◽

Cited By ~ 36

Author(s):

M. Rosolowsky ◽

W. B. Campbell

Keyword(s):

Arachidonic Acid ◽

Coronary Arteries ◽

Vascular Tone ◽

Epoxyeicosatrienoic Acids ◽

Lipoxygenase Inhibitor ◽

Physiological Processes ◽

Coronary Vascular Tone ◽

Cytochrome P 450 ◽

Endothelium Dependent Relaxation

Metabolites of arachidonic acid regulate several physiological processes, including vascular tone. The purpose of this study was to determine which metabolites of arachidonic acid are produced by bovine coronary arteries and which may regulate coronary vascular tone. Arachidonic acid induced a concentration-related, endothelium-dependent relaxation [one-half maximum effective concentration (EC50) of 2 x 10(-7) M and a maximal relaxation of 91 +/- 2% at 10(-5) M] of bovine coronary arteries that were contracted with U-46619, a thromboxane mimetic. The concentration of 6-ketoprostaglandin F1 alpha (6-keto-PGF1 alpha), a metabolite of prostaglandin I2 (PGI2), increased from 82 +/- 6 to 328 +/- 24 pg/ml with arachidonic acid (10(-5) M). Treatment with the cyclooxygenase inhibitor indomethacin attenuated arachidonic acid-induced relaxations by approximately 50% and blocked the synthesis of 6-keto-PGF1 alpha. PGI2 caused a concentration-related relaxation (EC50 of 10(-8) M and a maximal relaxation of 125 +/- 11% at 10(-7) M). BW755C, a cyclooxygenase and lipoxygenase inhibitor, inhibited arachidonic acid-induced relaxation to the same extent as indomethacin. When vessels were treated with both indomethacin and BW755C, the inhibition of relaxation was the same as either inhibitor alone. SKF 525a, a cytochrome P-450 inhibitor, reduced arachidonic acid-induced relaxation by approximately 50%. When SKF 525a was given in combination with indomethacin, the relaxation by arachidonic acid was almost completely inhibited. SKF 525a inhibited the synthesis of epoxyeicosatrienoic acids (EETs).(ABSTRACT TRUNCATED AT 250 WORDS)

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