Abstract
Plasma amino acid concentrations decrease in pregnancy despite increased requirements for both maternal and fetal protein accretion. There are few published data on changes in amino acid turnover in pregnancy. The aim of this study is to test the hypotheses that (1) whole body nonoxidative leucine disposal (NOLD) is higher and (2) whole body oxidative leucine disposal (OLD) is lower in the third trimester of pregnancy than in the nonpregnant state. After an overnight fast 8 pregnant women between 33 and 35 weeks gestation had a primed infusion of labeled [1- 13C] leucine and a prime dose of NaH 13CO 3. Carbon dioxide production was measured using indirect calorimetry. Gas chromatography-mass spectrometry was used to determine 13CO 2 enrichment of expired air and oxidative and nonoxidative leucine turnover by measuring 13C keto-isocaproate plasma enrichment, which reflects intracellular leucine enrichment. Women acted as their own controls after the puerperium. Whole body leucine turnover expressed per unit body weight was increased in pregnancy (median [interquartile range or IQR]: pregnant = 103.1 [14.9] v nonpregnant = 90.1 [10.9] μmol/kg/h). The mean (±SD) of the differences was 11.4 ± 5.6 μmol/kg/h, P = .0006. NOLD was increased in pregnancy (pregnant = 86.8 [10.1] v nonpregnant = 73.3 [9.5] μmol/kg/h). The mean (±SD) of the differences was 10.6 ± 5.4 μmol/kg/h, P = .0008. OLD was not significantly altered in pregnancy (pregnant = 17.3 [4.5] v nonpregnant = 15.91 [2.4] μmol/kg/h). The mean (±SD) of the differences was 0.84 ± 1.94 μmol/kg/h, P = .26. In conclusion, women have significantly higher NOLD in the third trimester of pregnancy than when not pregnant but there are no significant changes in OLD.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.