Artigo Acesso aberto Produção Nacional Revisado por pares

Mesenteric Microcirculatory Dysfunctions and Translocation of Indigenous Bacteria in a Rat Model of Strangulated Small Bowel Obstruction

2009; Elsevier BV; Volume: 64; Issue: 9 Linguagem: Inglês

10.1590/s1807-59322009000900013

ISSN

1980-5322

Autores

Fernando Luiz Zanoni, Simon Benabou, Karin Vicente Greco, Ana Carolina Ramos Moreno, José Wálber Miranda Costa Cruz, Fernando Filgueira, Marina Baquerizo Martinez, Luiz Francisco Poli de Figueiredo, Maurício Rocha e Silva, Paulina Sannomiya,

Tópico(s)

Renal function and acid-base balance

Resumo

Bacterial translocation has been shown to occur in critically ill patients after extensive trauma, shock, sepsis, or thermal injury. The present study investigates mesenteric microcirculatory dysfunctions, the bacterial translocation phenomenon, and hemodynamic/metabolic disturbances in a rat model of intestinal obstruction and ischemia. Anesthetized (pentobarbital 50 mg/kg, i.p.) male Wistar rats (250–350 g) were submitted to intestinal obstruction or laparotomy without intestinal obstruction (Sham) and were evaluated 24 hours later. Bacterial translocation was assessed by bacterial culture of the mesenteric lymph nodes (MLN), liver, spleen, and blood. Leukocyte-endothelial interactions in the mesenteric microcirculation were assessed by intravital microscopy, and P-selectin and intercellular adhesion molecule (ICAM)-1 expressions were quantified by immunohistochemistry. Hematocrit, blood gases, lactate, glucose, white blood cells, serum urea, creatinine, bilirubin, and hepatic enzymes were measured. About 86% of intestinal obstruction rats presented positive cultures for E. coli in samples of the mesenteric lymph nodes, liver, and spleen, and 57% had positive hemocultures. In comparison to the Sham rats, intestinal obstruction induced neutrophilia and increased the number of rolling (~2-fold), adherent (~5-fold), and migrated leukocytes (~11-fold); this increase was accompanied by an increased expression of P-selectin (~2-fold) and intercellular adhesion molecule-1 (~2-fold) in the mesenteric microcirculation. Intestinal obstruction rats exhibited decreased PaCO2, alkalosis, hyperlactatemia, and hyperglycemia, and increased blood potassium, hepatic enzyme activity, serum urea, creatinine, and bilirubin. A high mortality rate was observed after intestinal obstruction (83% at 72 h vs. 0% in Sham rats). Intestinal obstruction and ischemia in rats is a relevant model for the in vivo study of mesenteric microcirculatory dysfunction and the occurrence of bacterial translocation. This model parallels the events implicated in multiple organ dysfunction (MOD) and death.

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