Influence of arginine dietary supplementation on healing colonic anastomosis in the rat

INTRODUCTION: This study sought to determine whether dietary arginine influ ences colonic anastomotic healing in the rat model. METHODS: Three groups o f 42 Sprague-Dawley Mts were fed 0, 1, and 3 percent arginine diets for thr ee preoperative and three postoperative days. Animals underwent transection of the transverse colon with handsewn anastomosis. Subgroups of 14 animals in each dietary group were killed on postoperative Days 6, 10, or 14, and bursting pressures, histologic inflammation, and collagen content were comp ared. RESULTS: Mean anastomotic bursting pressures on postoperative Day 6 w ere lower for the 0 percent arginine group than the 1 and 3 percent arginin e groups (mean +/- standard error of the mean = 134 +/- 6 mmHg, 164 +/- 7 m mHg, and 166 +/- 7 mmHg, respectively; P < 0.0005). On Days 10 and 14, no s ignificant differences in bursting pressures were noted between arginine di ets. Mean bursting pressures on postoperative Day 6 (155 +/- 4 mmHg) were s ignificantly lower than on Days 10 (204 +/- 5 mmHg) and 14 (217 +/- 6 mmHg; P < 0.001) for all arginine diets. Microscopic evaluation of the anastomos es did not show significant differences in inflammation or collagen content between arginine diets. Collagen content in all dietary groups peaked at D ay 10. CONCLUSIONS: Perioperative arginine deficiency in the rat model is a ssociated with impaired anastomotic healing during the first week, as refle cted by lower bursting pressures. Arginine supplementation to 3 percent doe s not improve bursting pressures above those found in the usual 1 percent a rginine diet at 6, 10, or 14 days. Bursting pressures plateau by Day 10 reg ardless of perioperative dietary arginine, whereas collagen content peaks a t Day 10 after six-day perioperative arginine diet manipulation.