University of Patras
Επίδραση των δεξαμενών CO₂ στην εμφάνιση ισοτοπικού άνθρακα στην εκπνοή
Abstract
dc:descriptionIn ¹³CO₂ breath tests, based on ¹³C/¹²C ratio measurements, the appearance of ¹³C in the exhaled CO₂ is monitored after the administration of a ¹³C-labelled compound. Independently of the substrate used, the existence of the bicarbonate pool, in which the produced CO₂ enters before being exhaled, imposes a delay on the appearance of changes in the ¹³C/¹²C ratio. In order to estimate the nature and the magnitude of this delay we applied a three compartment model to describe the kinetics of the body bicarbonate pool and we evaluated the ¹³C/¹²C ratio of CO₂ entering that pool from the measured ¹³C/¹²C ratio in the exhaled CO₂ after oral intake of "naturally labelled" 13C-glucose at rest and during muscular exercise. Our results demonstrate that: 1) at rest, discrepancies between total carbohydrates consumption and exogenous glucose oxidation concerning the peak occurrence time, as well as the absolute quantities, can be adequately explained by the interference of the bicarbonate stores. The influence of bicarbonate pool should be taken into account when the evolution of exogenous glucose oxidation is to be studied quantitatively at rest and 2) during moderate exercise, there is not influence of bicarbonate pool in the occurrence of labelled CO₂ and furthermore on the estimation of exogenous glucose oxidation. The influence of bicarbonate pool is directly dependent on the intensity of the muscular exercise and should be taken into account when the evolution of exogenous glucose oxidation is to be studied quantitatively at low intensity effort.
Degree
thesis:*- Grantor dc:publisher
- University of Patras
- Year dc:date
- 1991
Author and committee
dc:creator, dc:contributor.*- Authors dc:creator
-
- Sphiris, N.
- Σφυρής, Νικόλαος
Subjects
dc:subject × 13Rights
- Language dc:language
- gre
Identifiers
dc:identifier.*- Identifier
- 10.12681/eadd/1732
- OAI identifier oai:identifier
- oai:10442/1732