Fever, antipyretics and serum iron levels in rabbits

The intracerebroventricular (i.c.v.) injection of bacterial endotoxin (Shigella dysenteriae) produces a rise in deep-body temperature in rabbits. The increase in body temperature was partially inhibited by polymyxin B (P), and completely suppressed by ketoprofen (K). The systemic injection of bacterial endotoxins (Shigella dysenteriae or Salmonella typhosa) elicited an elevation of body temperature in rabbits which was partially blocked by polymyxin B and completely antagonized by ketoprofen. Serum iron concentration fell in rabbits treated with Salmonella typhosa endotoxin and rose after injections of ketoprofen, polymyxin B, indomethacin and ketoprofen plus endotoxin (En). However, the total increases in serum iron levels were higher after antipyretics than after ketoprofen plus endotoxin treatment. These results show that the antipyretics antagonized the rise in body temperature and the fall in serum iron concentration induced by bacterial endotoxin and all the drugs used in this study to induce antipyresis increased serum iron levels.