Macrophage treatment in suckling rat endotoxic shock.

Gram-negative sepsis/septic shock in the human newborn continues to be a severe medical problem because of significant mortality and morbidity. Since macrophages detoxify endotoxin, a decreased number of macrophages may contribute to the newborn's sensitivity to endotoxin. In this study, peritoneal macrophages were used for the treatment of endotoxic shock in 10-day-old rats, and 24-hr mortality, plasma glucose, and lactate concentrations were monitored. Peritoneal macrophages were harvested from adult or 10-day-old rats. Caseinate-stimulated macrophages from adult and 10-day-old rats significantly decreased the mortality of 10-day-old rat endotoxic shock from 90% to 37.5% and 44.4%, respectively. Resident macrophages from adult and 10-day-old rats also decreased the mortality from 90% to 12.5% and 45.4%, respectively. Peritoneal macrophages from adult rats significantly ameliorated hypoglycemia during endotoxic shock in a dose-dependent manner. Macrophage treatment decreased plasma endotoxin concentration (P < 0.05). Macrophage treatment was important for host defense.