Table 3—

Free amino acid pool and glutathione (GSH) levels in the diaphragm and quadriceps femoris#

Control diaphragmCOPD group
DiaphragmVastus lateralis
Glu µmol·kg WW−14161±5884253±5581584±333*
GSH µmol·kg WW−12257±1602140±2281226±201*
Glu/GSH1.8±1.52.0±0.51.3±0.1*
Asn µmol·kg WW−1282±8280±32157±23*
Ser µmol·kg WW−1650±102748±104451±79*
Gln µmol·kg WW−19328±8988808±11329097±1306
Gly µmol·kg WW−11025±54966±78819±122
Thr µmol·kg WW−1760±50812±91540±79*
His µmol·kg WW−1394±49405±51339±59
Cit µmol·kg WW−187±1756±9106±26*
Ala µmol·kg WW−12388±2462065±1841327±240**
Tau µmol·kg WW−15835±6977031±7597332±1544
Arg µmol·kg WW−1442±66468±56375±90
α‐ABA µmol·kg WW−156±745±437±6
Tyr µmol·kg WW−183±899±974±11+
Val µmol·kg WW−1341±35349±38271±32
Met µmol·kg WW−173±1983±2055±21
Ile µmol·kg WW−1116±13118±1384±10
Phe µmol·kg WW−1149±27124±1480±12
Trp µmol·kg WW−1324±49315±80184±35
Leu µmol·kg WW−1208±24184±14140±19*
Orn µmol·kg WW−1154±18155±19163±44
Lys µmol·kg WW−1693±75690±95694±176
BCAAs µmol·kg WW−1633±65651±60493±66
Total AAs µmol·kg WW−130467±304931729±309128836±4388
  • Data are presented as mean±sem

  • COPD: chronic obstructive pulmonary disease

  • Glu: glutamate

  • GSH: reduced glutathione

  • Asn: asparagines

  • Ser: serine

  • Gln: glutamine

  • Gly: glycine

  • Thr: threonine

  • His: histidine

  • Cit: citrulline

  • Ala: alanine

  • Tau: taurine

  • Arg: arginine

  • α‐ABA: alpha-aminobutyric acid

  • Tyr: tyrosine

  • Val: valine

  • Met: methionine

  • Ile: isoleucine

  • Phe: phenylalanine

  • Trp: tryptophan

  • Leu: leucine

  • Orn: ornithine

  • Lys: lysine

  • BCAA: branched-chain amino acid (AA)

  • WW: wet weight

  • #: vastus lateralis

  • : p=0.08

  • +: p=0.07

  • *: p<0.05

  • **: p<0.01 versus COPD group diaphragm