Surfactant protein C metabolism in human infants and adult patients by stable isotope tracer and mass spectrometry.
Anal Bioanal Chem
; 406(25): 6225-33, 2014 Oct.
Article
en En
| MEDLINE
| ID: mdl-25182966
ABSTRACT
Surfactant protein C (SP-C) is deemed as the surfactant protein most specifically expressed in type II alveolar epithelial cells and plays an important role in surfactant function. SP-C turnover in humans and its meaning in the clinical context have never been approached. In this study, we used mass spectrometry to investigate SP-C turnover in humans. We studied four infants and eight adults requiring mechanical ventilation. All patients had no lung disease. Patients received a 24-h continuous infusion of (13)C-leucine as precursor of SP-C, and serial tracheal aspirates and plasma samples were obtained every 6 h till 48 h. SP-C was isolated from tracheal aspirates by sorbent-phase chromatography. (13)C-leucine SP-C enrichment could be successfully measured in three infant and in four adult samples by using mass spectrometry coupled with a gas chromatographer. Median SP-C fractional synthesis rate, secretion time, and peak time were 15.7 (14.1-27.5)%/day, 6.0 (4.7-11.5) h, and 24 (20-27) h. In conclusion, this study shows that it is feasible to accurately determine SP-C turnover in humans by stable isotopes.
Texto completo:
1
Bases de datos:
MEDLINE
Asunto principal:
Espectrometría de Masas
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Proteína C Asociada a Surfactante Pulmonar
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Marcaje Isotópico
Tipo de estudio:
Evaluation_studies
Límite:
Adult
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Aged
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Female
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Humans
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Infant
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Male
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Middle aged
Idioma:
En
Revista:
Anal Bioanal Chem
Año:
2014
Tipo del documento:
Article