ENDOTOXIN-CHALLENGES PRECOCIAL NEONATES AND IRON CHANGES

In adult mammals fever is associated with the reduction of blood plasm a iron level. Immature mammals, however, show either a decrease (preco cial animals such as guinea pig neonates) or a lack of reduction (altr icial animals such as human neonates) of plasma iron in response to en dotoxin. In order to determine whether this difference is connected wi th maturity just after delivery, plasma iron concentration, hematocrit , body temperature and body mass were measured in rat pups injected wi th E. coli endotoxin in doses of 50 or 200 mu g kg(-1). Rat pups, like human neonates, are altricial animals. In 7-day-old rats injection of LPS led to a dose-dependent decrease in plasma iron level. The fall i n plasma iron was accompanied by changes in body temperature and body mass. The results showed that plasma iron response to endotoxin in alt ricial rat neonates is similar to that observed in precocial guinea pi g pups.