The impact of arginine on bacterial translocation in an intestinal obstruction model in rats.
OBJECTIVE
Arginine has been shown to have multiple beneficial metabolic and immunologic effects in stress situations. Supplementation of arginine has been shown to promote wound healing and intestinal mucosal recovery after trauma, ischemia or intestinal resection. Bacterial translocation has also been evaluated although with conflicting results and using different assessing techniques. Therefore, the aim of this study was to evaluate the effects of arginine on bacterial translocation in an intestinal obstruction model in rats using Escherichia coli labeled with 99mTechnetium.


METHODS
Male Wistar rats (250-350 g) were randomized to receive conventional chow, diet supplemented with pure arginine or diet supplemented with an immunonutrition enteral formula, enriched with arginine, omega-3 fatty acid and RNA. After 7 days, the animals were anesthetized. Terminal ileum was isolated and a ligature was placed around it. E. coli labeled with 99mTechnetium (99mTc-E. coli) was inoculated into the intestinal lumen (terminal ileum). After 24 h, the animals were sacrificed. Blood, mesenteric lymph nodes (MLN), liver, spleen and lungs were removed for radioactivity determination.


RESULTS
Arginine supplementation (300 mg/day, 600 mg/day or present in the enteral formula) reduced the level of bacterial translocation when compared with the control group (p<0.05). This was shown by significantly decrease uptake of 99mTc-E. coli in blood, MLN, liver, spleen and lungs of the animals in the experimental groups (p < 0.05).


CONCLUSIONS
These results have shown that arginine was able to decrease bacteria translocation despite intestinal obstruction. There are several mechanisms which might explain the role of arginine and these will be the subject of future studies.
Quirino
Iara Eliza Pacífico
IE
School of Pharmacy, Federal University of Minas Gerais, Brazil. iarapacifico@yahoo.com.br
Correia
Maria Isabel Toulson Davisson
MI
Cardoso
Valbert Nascimento
VN
D000818:Animals; D001120:Arginine / Q000494:pharmacology*; D018988:Bacterial Translocation / Q000187:drug effects*; D004195:Disease Models, Animal; D004305:Dose-Response Relationship, Drug; D004750:Enteral Nutrition; D004926:Escherichia coli / Q000502:physiology*; D015525:Fatty Acids, Omega-3 / Q000008:administration & dosage; D006801:Humans; D007415:Intestinal Obstruction / Q000382:microbiology* / Q000503:physiopathology; D008099:Liver / Q000382:microbiology; D008168:Lung / Q000382:microbiology; D008198:Lymph Nodes / Q000382:microbiology; D008297:Male; D009747:Nutritional Physiological Phenomena; D012313:RNA / Q000008:administration & dosage; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D013154:Spleen / Q000382:microbiology; D013667:Technetium
D015525:Fatty Acids, Omega-3; D012313:RNA; D013667:Technetium; D001120:Arginine