Effects of 5,7-dihydroxytryptamine and 6-hydroxydopamine on fever response in conscious rats

The effects of 5,7-dihydroxytryptamine (5,7-DHT) and 6-hydroxydopamine (6-OHDA) on the febrile response to E. coli lipopolysaccharide (LPS) of unanesthetized rats examined. Depleting serotonin (5-HT) in brain with 5,7-DHT produced an attenuation in fever response to LPS, while depleting noradrenaline (NA) content in the preoptic area with 6-OHDA produced an opposite effect. However, 6-OHDA when given intraventricularly (icv) was without any significant effect on fever response to LPS. Presented data indicate that alterations in both noradrenergic and serotoninergic system of the rat brain affect the febrile response response to bacterial pyrogen. Moreover, one might conclude that integrity of noradrenergic neurons in central nervous system (CNS) in the rat is not essential for appearance of pyrogen fever.