Development of hyperthermia and hyperalgesia following intracerebroventricular administration of endotoxin in the rat: effect of kinin B1 and B2 receptor antagonists

Abstract

The present study investigated the development of hyperthermia and thermal and mechanical hyperalgesia following i.c.v. injections ofE. coli lipopolysaccharide (LPS) in rats. LPS increased core temperature and this was prevented by i.c.v. administration of HOE 140, a kinin B2 receptor antagonist or by indomethacin i.c.v. or i.v. B1 receptor antagonists had no effect. LPS induced thermal and mechanical hyperalgesia which was reversed by i.c.v. HOE 140 and indomethacin i.c.v. and i.v., but not by B1 receptor antagonists. These results indicate that injections of endotoxin to the CNS induces hyperthermia and hyperalgesia and that kinins, acting on centrally located B2 receptors, and prostanoids are involved.