Skeletal muscle amino acid and myofibrillar protein mRNA response to thermal injury and infection.
Skeletal muscle changes associated with severe injury were investigated in male Wistar rats subjected to 30% full thickness scald injury (burn) and thermal injury followed by immediate colonization with 10(8) colony-forming units of Pseudomonas aeruginosa (BI). Freely fed animals (FF) and animals pair fed to the BI animals (PF) served as controls. Thermal injury in conjunction with infection produced a rapid and sustained muscle cellular membrane depolarization (transmembrane potential difference at 12 h after injury: FF 92.1 +/- 0.3 and BI 85.2 +/- 2.3 mV; P less than 0.05). This was followed by body weight loss and skeletal muscle protein wasting (gastrocnemius protein at 7 days: FF 0.35 +/- 0.01 and BI 0.16 +/- 0.03 g; P less than 0.05) and intracellular high-energy phosphate depletion (ATP at 10 days: FF 6.6 +/- 0.4 and BI 4.5 +/- 0.4 mumol/g tissue; P less than 0.05). These body and cellular changes were not accounted for by the anorexia alone. Marked alterations in intracellular free amino acids were also noted in the BI group characterized by increases in levels of all amino acids (total intracellular free amino acids at 7 days: FF 51 +/- 7 and BI 91 +/- 12 mM; P less than 0.05) except intracellular glutamine (at 7 days: FF 6.0 +/- 0.2 and BI 2.4 +/- 0.6 mM; P less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)
Fong
Y M
YM
Department of Surgery, New York Hospital-Cornell Medical Center, New York 10021.
Minei
J P
JP
Marano
M A
MA
Moldawer
L L
LL
Wei
H
H
Shires
G T
GT
Shires
G T
GT
Lowry
S F
SF
D000199:Actins / Q000235:genetics*; D000255:Adenosine Triphosphate / Q000378:metabolism; D000596:Amino Acids / Q000378:metabolism*; D000818:Animals; D002056:Burns / Q000503:physiopathology*; D004247:DNA / Q000378:metabolism; D004734:Energy Metabolism; D008564:Membrane Potentials; D009124:Muscle Proteins / Q000378:metabolism; D009132:Muscles / Q000502:physiology / Q000503:physiopathology*; D009218:Myosins / Q000235:genetics*; D010725:Phosphocreatine / Q000378:metabolism; D011188:Potassium / Q000378:metabolism; D011552:Pseudomonas Infections / Q000503:physiopathology*; D012313:RNA / Q000378:metabolism; D012333:RNA, Messenger / Q000235:genetics*; D051381:Rats; D011919:Rats, Inbred Strains; D012016:Reference Values; D012964:Sodium / Q000378:metabolism
D000199:Actins; D000596:Amino Acids; D009124:Muscle Proteins; D012333:RNA, Messenger; D010725:Phosphocreatine; D012313:RNA; D000255:Adenosine Triphosphate; D004247:DNA; D012964:Sodium; D009218:Myosins; D011188:Potassium