Arginina como imunomodulador da resposta inflamatória pulmonar em camundongos com peritonite induzida

Abstract

INTRODUCTION: Sepsis due to secondary peritoneal infections is one of the main causes of death in the surgical clinic and in intensive care units. Several factors, such as the immunocompetence of the individual and the virulence of the bacterial strain have been important cause in the increase of the severity of this affection. Among its complications are the involvement of terminal organs, such as lung, with the occurrence of pneumonia and shock lung. In experimental studies, administration of arginine prolonged the survival of animals with induced peritonitis, perhaps by reducing inflammation and stimulating the immune state. PURPOSE: To evaluate the pulmonary inflammatory response in mice with induced peritonitis and treated with lavage of the peritoneal cavity, complemented with systemic administration of arginine. METHOD: Thirty-two Balb/cAnNCrl mice distributed in the following experimental groups were used: L-PL (n=8), laparotomy and placebo administration; L-AR (n = 8), laparotomy and administration of arginine; P-PL (n=8), induction of peritonitis and administration of placebo; P-AR (n=8), induction of peritonitis and administration of arginine. The animals were anesthetized and the peritonitis was induced by ligature and cecal section technique. The abdomen was then closed, and after ninety minutes, new laparotomy, lavage of the peritoneal cavity, volume resuscitation, antibiotic therapy and subcutaneous administration of arginine at a dose of 0.95 g / kg were performed shortly after closure of the peritoneal cavity. After six hours of induction of peritonitis, the animals were killed and lung fragments collected for histological and morphometric analysis. RESULTS: In the P-AR group (arginine peritonitis) there was a significant reduction in the mean nuclear count and histological parameters evaluated in the lung when compared to P-PL group (peritonitis with placebo). CONCLUSION: Arginine administration, at a dose of 0.95 g / kg, reduced early lung injury in mice with induced peritonitis.