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A novel approach to real-time monitoring of erythrocyte ATP release as a function of hypoxia

dc.contributor.authorSmith, Meghan E., author
dc.contributor.authorDinenno, Frank, advisor
dc.contributor.authorLark, Daniel, committee member
dc.contributor.authorAmberg, Gregory, committee member
dc.date.accessioned2021-01-11T11:20:07Z
dc.date.available2021-01-11T11:20:07Z
dc.date.issued2020
dc.description.abstractBackground: Matching blood flow to tissue oxygen demand is essential for maintaining metabolic homeostasis and sustaining human life. Recent studies suggest that red blood cells (RBCs) play a role in local vasodilatory signaling by releasing ATP in response to hypoxia. RBC ATP release and overall function are impaired with age and disease. Until now, luciferin/luciferase bioluminescence is the only method described to quantify ATP release from RBCs. Here, we describe a novel approach where ATP release is measured as a function of hypoxia continuously and in real time using an Oroboros Oxygraph O2K respirometer. Purpose: This report describes the development and application of this new approach. Methods: We obtained blood samples from 10 healthy, young adults (18-35y) via venipuncture. Washed RBCs were diluted to 5% hematocrit and added to the glass chamber of a calibrated Oxyfluorimeter along with 5μM Mg-G. Nitrogen gas was constantly injected into the chamber at 1 ml/min to decrease PO2. An LED-based fluorescence detection device monitored Mg-G fluorescence, which was used to calculate extracellular [ATP]. Results: When 5% HCT RBCs were exposed to 30 minutes of hypoxia, Mg-G fluorescence (V) continuously increased. During 30 minutes of progressive hypoxia, PO2 in the chamber decreased from 121.9 ± 1.3 to 9.8 ± 0.8 mmHg, and D extracellular [ATP] from normoxia (μM) increases from 0 to 6,985.0 ± 793.6 μM. Extracellular [ATP] accumulates markedly when PO2 in the chamber reaches 50.60 ± 1.52 mmHg. Conclusion: Using this novel method, we identified a PO2 threshold at which extracellular ATP accumulates rapidly, which is consistent with the range of PO2 that elicits Hb desaturation in RBCs. This approach may allow for detailed mechanistic studies into the relationship between hypoxia, Hb desaturation, and RBC ATP release.
dc.format.mediumborn digital
dc.format.mediummasters theses
dc.identifierSmith_colostate_0053N_16299.pdf
dc.identifier.urihttps://hdl.handle.net/10217/219519
dc.languageEnglish
dc.language.isoeng
dc.publisherColorado State University. Libraries
dc.relation.ispartof2020-
dc.rightsCopyright and other restrictions may apply. User is responsible for compliance with all applicable laws. For information about copyright law, please see https://libguides.colostate.edu/copyright.
dc.titleA novel approach to real-time monitoring of erythrocyte ATP release as a function of hypoxia
dc.typeText
dcterms.rights.dplaThis Item is protected by copyright and/or related rights (https://rightsstatements.org/vocab/InC/1.0/). You are free to use this Item in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights-holder(s).
thesis.degree.disciplineHealth and Exercise Science
thesis.degree.grantorColorado State University
thesis.degree.levelMasters
thesis.degree.nameMaster of Science (M.S.)

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