The rate of protein synthesis was assessed in muscle, lymphocytes, and albumin in healthy volunteers administered an infusion of 6.0 micrograms cortisol +3.0 ng glucagon +0.5 nmol epinephrine min-1.kg-1. Protein synthesis in muscle tissue was not sensitive to the immediate effects of hormone infusion, but decreased significantly by 18 hours after the infusion had ceased (1.77% +/- 0.12% per day v 1.29% +/- 0.10%, P < .05). The rate of protein synthesis in lymphocytes was acutely sensitive to the effect of the hormone infusion, decreasing from 7.15% +/- 1.02% per day to 2.47% +/- 0.5% (P < .05). However, measurements made 18 hours after the end of the hormone infusion indicated that lymphocyte protein synthesis returned to the preinfusion rates. The rate of albumin synthesis was unaltered during infusion of the stress hormones, but was significantly increased when measured 18 hours after ending the hormone infusion (6.84% +/- 0.43% per day v 7.99% +/- 0.45%, P < .05). Thus, tissues respond differently to stress hormone infusion, demonstrating the importance of studying multiple organ systems when assessing the regulation of protein metabolism.