Premium
In vivo protein synthesis of circulating human T lymphocytes does not respond to a cortisol challenge within 24 h
Author(s) -
Januszkiewicz A.,
Essén P.,
Mcnurlan M. A.,
Ringdén O.,
Wernerman J.,
Garlick P. J.
Publication year - 2000
Publication title -
acta anaesthesiologica scandinavica
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.738
H-Index - 107
eISSN - 1399-6576
pISSN - 0001-5172
DOI - 10.1034/j.1399-6576.2000.440212.x
Subject(s) - in vivo , medicine , immunocompetence , saline , endocrinology , stimulation , lymphocyte , in vitro , immunology , biochemistry , biology , immune system , microbiology and biotechnology
Background: Although immunocompetence is often measured by assessing responsiveness of lymphocytes to mitogenic stimulation in vitro , this approach may not reflect the in vivo situation. The aim of this investigation was to determine in vivo the protein synthesis rate (FSR) in isolated T lymphocytes and to study the effect of a short‐term cortisol infusion on FSR. Methods: Healthy volunteers (n=24) were randomised into 4 groups. A continuous cortisol infusion (6 μg kg −1 min −1 ) during 6 h was given to groups 1 and 2, whereas groups 3 and 4 served as control groups and received saline infusion. Protein synthesis was studied before and after 6 h of the cortisol/saline infusion (groups 1 and 3) or 24 h after the start of the infusion (groups 2 and 4). FSR was determined in vivo by the flooding method. The isotopic enrichment of phenylalanine in plasma and lymphocyte protein was determined with gas chromatography‐mass spectrometry. Results: The FSR in T lymphocytes was 13.6±0.9%/24 h as a mean value (±SD) of the first determination in 4 groups. There was no significant difference in FSR from the baseline value immediately after the cortisol infusion (group 1: 13.3±1.4%/24 h vs 13.5±2.8%/24 h) or 24 h after the start of the infusion (group 2: 13.6±0.7%/24 h vs 12.3±2.4%/24 h). Conclusion: The metabolic activity of circulating T lymphocytes, as reflected by a quantitative measurement of in vivo protein synthesis of human T lymphocytes, was not affected by the increased level of cortisol.