The antipyretic effect of NG-nitro-L-arginine methyl ester is related to its influence on metabolism

Thermoregulatory responses (rectal and ear skin temperatures, metabolic rate, respiratory rate), after treatment with N-G-nitro-L-arginine methyl ester (L-NAME), were investigated in normothermic and febrile rabbits at an ambient temperature of 20 +/- 1 degrees C. In endotoxin challenged rabbits, L-NAME (25 mg/kg i.v.) given 30 min before LPS (1 mu g/kg i.v.) significantly reduced fever response, while did not influence body temperature in saline treated animals. The antipyretic action of L-NAME was caused mainly due to inhibition of metabolic rate. (C) 2000 Elsevier Science Ltd. All rights reserved.