Skeletal muscle glutathione after surgical trauma.
AUTOR(ES)
Luo, J L
RESUMO
OBJECTIVE: The authors investigate the effect of surgical trauma on skeletal muscle concentrations of glutathione in patients undergoing selective abdominal surgery. SUMMARY BACKGROUND DATA: The posttraumatic state is accompanied by characteristic changes in the pattern of free amino acids and a decline of protein synthesis in human skeletal muscle. Glutathione has multiple metabolic functions that are involved in cellular homeostasis. It is unknown how surgical trauma affects the glutathione metabolism of skeletal muscle in surgical patients. METHODS: Eight patients undergoing elective abdominal surgery were investigated. Percutaneous muscle biopsies and blood samples were taken before operation and at 6, 24, and 48 hours after operation. The concentrations of glutathione were determined in muscle tissue, plasma, and whole blood, as well as the concentrations of the related amino acids in muscle and plasma. RESULTS: In skeletal muscle, the levels of both reduced and total glutathione decreased by 40% (p<0.01) at 24 hours and remained low at 48 hours after operation compared with the preoperative values. The glutathione concentration in plasma was 20% lower after operation compared with the concentration before operation (p<0.05). There were no changes at the whole blood levels of glutathione. Tissue glutamate and glutamine decreased significantly after operation (p<0.001), whereas intracellular cysteine and glycine remained unchanged. CONCLUSIONS: Skeletal muscle glutathione deficiency occurs after surgical trauma. This may lead to an increase in the susceptibility to intracellular oxidative injury.
