Dynamic accumulation of neutrophils in lungs and visceral organs during early abdominal sepsis in the pig.

Abstract

Activation and accumulation of polymorphonuclear leukocytes (PMNs, neutrophils) in the lungs is considered an important mechanism in the pathogenesis of pulmonary dysfunction in association with sepsis. It probably constitutes only part of a general cellular response; and a corresponding reaction has been implicated in other organs during sepsis (e.g., the liver). In this experiment a model was developed that allows study of the dynamic PMN reaction in the lungs and visceral organs during early abdominal sepsis. The animals were divided into two groups. In the septic group (n = 8) a bacterial challenge was attempted through the intraperitoneal administration of Escherichia coli (1 x 10(11)/kg). Five animals served as controls. All animals in the septic group developed bacteremia, leukopenia, and a hypodynamic circulatory response. PMNs were selectively labeled with 111In-oxine. The activity over the organs was followed dynamically with a gamma camera. The animals subjected to peritonitis exhibited a significant increase in 111In-oxine activity (i.e., neutrophil trapping) in the lungs, compared to the controls at 40 minutes and onward during the observation period. A similar picture was seen over the liver and abdomen, with significance after 70 minutes. The findings in this study indicate that accumulation of PMNs is an early phenomenon not only in the lungs but also in the liver during the development of sepsis. The present model offers possibilities for further studies of the cellular reactions during sepsis.