Is there a circulating proteolysis-inducing factor during sepsis?
P. O. Hasselgren, J. H. James, D. W. Benson, S. Li and J. E. Fischer
Department of Surgery, University of Cincinnati Medical Center, OH 45267-0558.
Muscles from fed or 72-hour fasted rats were incubated in the presence of
plasma from septic rats, recombinant interleukin 1 alpha (rIL-1 alpha), or
recombinant tumor necrosis factor alpha (rTNF alpha), and breakdown of
total and myofibrillar protein was assessed by determining release of
tyrosine and 3-methylhistidine, respectively. Septic plasma stimulated
total protein breakdown in muscles from 72-hour fasted rats by 10% to 20%,
while myofibrillar protein breakdown was not affected. When septic plasma
was added to muscles from fed rats, neither tyrosine nor 3-methylhistidine
release was altered. Various concentrations of recombinant interleukin 1
alpha or recombinant tumor necrosis factor alpha did not affect total or
myofibrillar protein breakdown. Since septic plasma did not stimulate
myofibrillar protein breakdown, the role of a circulating factor for muscle
proteolysis during sepsis remains unclear.
