Behavioural and body temperature effects of meningococcal lipopolysaccharide after intraventricular injection in adult fowls Gallus domesticus.

The effects of the meningococcal lipopolysaccharide (LPS), given into the II cerebral ventricle of adult fowls, were studied on behaviour and body temperature. Immediately after the administration a marked and dose- dependent behavioural sedation or sleep lasting over 2 hours or more according to the dose was observed. The body temperature effects of LPS were biphasic, i.e. and immediate initial phase of hypothermia lasting about 100 min, followed by a longer-lasting fever response. A pretreatment with phentolamine, an antagonist at alpha-adrenoceptors prevented the hypothermic phase following the endotoxin administration. In conclusion, present experiments show that in comparison to 0-somatic antigen of Shigella dysenteriae, meningococcal endotoxin possesses more marked behavioural effects and a different profile in body temperature effects.