The effect of XXXX on small-intestinal mucosal protein synthesis in @entity1 after surgical stress.

@entity1 @entity6 @entity4628 @entity2124 @entity3190 @entity1162 @entity413
@entity3190 cannot stimulate intestinal protein synthesis in healthy individuals but does so in conditions characterized by an altered somatotropic axis such as @entity6 . Only in a state of @entity2124 resistance (high @entity2124 but low insulin like growth factor [IGF-1] concentrations), extra insulin may acutely reverse the impaired, growth-hormone-induced IGF-1 release, thereby exerting anabolic actions at the intestinal tract. @entity2124 resistance can be also found in @entity1 after surgical stress. Therefore, we wanted to test the hypothesis whether @entity3190 would stimulate ileal protein synthesis in the latter condition. Mass spectrometry techniques (capillary gas chromatography/combustion isotope ratio mass spectrometry) were used to directly determine the incorporation rate of 1-[(13)C]-leucine into ileal mucosal protein. All subjects had an ileostomy, which allowed easy @entity4628 , and consecutive sampling from the same tissue was performed during continuous isotope infusion (0.16 mumol/kg min). Isotopic enrichments and fractional protein synthesis were determined at baseline (period I) and after a 4-hour @entity413 infusion (170 mg/kg/h) or after infusion of saline (control group) (period II). In controls, ileal protein synthesis declined significantly during @entity1162 (period I: 1.11 +/- 0.14%/h, period II: 0.39 +/- 0.13%/h, p < .01). In contrast, ileal protein synthesis remained constant during @entity413 infusion (period I: 1.32 +/- 0.35%/h, period II: 1.33 +/- 0.21%/h, n.s. vs period I, but p < .005 vs the corresponding value at the end of period II in the control group). Using the continuous tracer infusion technique, ileal protein synthesis seemingly declines over a short time in control subjects. We found evidence that this artificial decline was due to mass effects of a rapidly turning over mucosa protein pool in which an isotopic plateau was reached during the experiment and of which the size amounted to approximately 4% of the total mixed protein pool. Maintenance of ileal protein synthesis during @entity413 infusion therefore indicates a rise of ileal protein synthesis in a slowly turning over protein pool. This effect in postsurgical @entity1 would be compatible with the concept of intestinal insulin action to depend on the specific clinical state (eg, @entity2124 resistance).
