MK801 impairs thermoregulation in the heat.
The effects of MK801 (dizocilpine), a glutamate NMDA receptor antagonist, on thermoregulation in the heat were studied in awake rats exposed to 40 degrees C ambient temperature until their body core temperature reached 43 degrees C. Under these conditions, MK801-treated rats exhibited enhanced locomotor activity and a steady rise in body core temperature, which reduced the heat exposure duration required to reach 43 degrees C. Since MK801-treated rats also showed increased striatal dopaminergic metabolism at thermoneutrality, the role of dopamine in the MK801-induced impairment of thermoregulation in the heat was determined using co-treatment with SCH23390, a dopamine D1 receptor antagonist. SCH23390 normalized the locomotor activity in the heat without any effect on the heat exposure duration. These results suggest that the MK801-induced impairment of thermoregulation in the heat is related to neither a dopamine metabolism alteration nor a locomotor activity enhancement.
Canini
Frédéric
F
Département des facteurs humains, Centre de recherches du Service de santé des armées (CRSSA), La Tronche, France. fredericcanini@crssa.net
Simler
Nadine
N
Bourdon
Lionel
L
D000818:Animals; D001552:Benzazepines / Q000494:pharmacology; D001833:Body Temperature Regulation / Q000187:drug effects*; D003342:Corpus Striatum / Q000378:metabolism; D016291:Dizocilpine Maleate / Q000633:toxicity*; D004298:Dopamine / Q000378:metabolism; D018492:Dopamine Antagonists / Q000494:pharmacology; D018690:Excitatory Amino Acid Agonists / Q000009:adverse effects*; D008297:Male; D009043:Motor Activity / Q000187:drug effects; D018696:Neuroprotective Agents / Q000009:adverse effects*; D051381:Rats; D017207:Rats, Sprague-Dawley
D001552:Benzazepines; D018492:Dopamine Antagonists; D018690:Excitatory Amino Acid Agonists; D018696:Neuroprotective Agents; D016291:Dizocilpine Maleate; D004298:Dopamine