BOTH GROWTH-HORMONE AND EXOGENOUS GLUTAMINE INCREASE GASTROINTESTINALGLUTAMINE UPTAKE IN TRAUMA

Objective The authors studied the effect of exogenous glutamine (GLN), with and without growth hormone (GH), pretreatment, on gastrointestin al, hepatic, femoral, and renal GLN fluxes. Summary Background Data Gr owth hormone treatment increases gastrointestinal uptake of GLN despit e a reduced skeletal muscle and whole body release. Methods Piglets we re randomized to a GH+GLN group (n=8), a GLN group (n=8), a GH group ( n=8), and a control group (CON; n=8). Genotropin (Pharmacia, Stockholm , Sweden; 24 international units; correspondingly saline in the GLN an d the CON group) was given daily 3 days before and at the onset of tra uma (surgery). Organ fluxes and whole body release of GLN were determi ned 1 and 5 hours after surgery. An infusion of GLN 36 mu g/kg per min ute was started after the first measurement in the GH+GLN and the GLN groups. Results Both GH treatment and exogenous GLN increased gastroin testinal GLN uptake (p=0.001 and p=0.02, respectively). Growth hormone treatment reduced hepatic GLN uptake (p=0.001). Hepatic GLN uptake wa s lower in the GH+GLN group versus the GH group (p=0.02), but not in t he GLN group versus the CON group (p=0.98). Growth hormone treatment r educed femoral and whole-body GLN release (p=0.0001 and p=0.02, respec tively). Renal GLN uptake was higher in the two GH-treated groups (p=0 .003). Conclusion Both exogenous GLN and GH increased gastrointestinal GLN uptake, and the combination was additive. In contrast to exogenou s GLN, GH reduced hepatic uptake and consequently facilitated the incr eased gastrointestinal GLN uptake that occurred despite reduced femora l and whole-body release.