ObjectiveTo investigate the effect of sepsis on the intestinal absorption of arginine.DesignControlled, nonintervention study.SettingSurgical research laboratories of Sinai Hospital of Baltimore.SubjectsMale Sprague-Dawley rats.InterventionsExperimental sepsis induced by cecal ligation and puncture or intraperitoneal injection of lipopolysaccharide.Measurements and Main ResultsSepsis assessed by peritoneal and blood cultures. Intestinal absorption estimated by measuring the transfer of3H-arginine by everted jejunal sacs prepared from septic and control animals (n = 6 per group) at multiple time points after the induction of sepsis (6, 12, 24, 48, and 72 hrs after cecal ligation and puncture; 6 and 12 hrs after intraperitoneal injection of lipopolysaccharide). Induction of peritonitis in the rat by cecal ligation and puncture significantly reduced the in vitro uptake of arginine by everted jejunal sacs at 12, 24, and 48 hrs after laparotomy. Arginine transfer by everted jejunal sacs was also significantly reduced in rats as early as 6 hrs after intraperitoneal injection of endotoxin (endotoxin 273 +/- 14; saline 377 +/- 14 nmol/sac/hr). Data are expressed as mean +/- SEM. Recovery from sepsis was associated with normalization of arginine transfer by intestinal sacs.ConclusionsExperimental sepsis, induced by either cecal ligation and puncture or intraperitoneal injection of lipopolysaccharide, resulted in impaired intestinal amino acid uptake. Impaired intestinal arginine absorption may explain the lack of benefit of enteral, compared with parenteral, arginine therapy on survival from a septic insult.(Crit Care Med 1995; 23:1227-1232)