DISTINCT EFFECTS OF MK-801 AND (+ -)-2-AMINO-5-PHOSPHONOPENTANOIC ACID ON N-METHYL-D-ASPARTATE-INDUCED RISE OF BRAIN TEMPERATURE IN RATS/

Intracerebroventricular (i.c.v.) administration of N-methyl-D-aspartat e (NMDA) caused a biphasic rise of brain temperature, namely, a rapid, early rise and a larger, late rise, in urethane-anesthetized rats. I. c.v. pretreatment with a noncompetitive NMDA receptor antagonist, MK-8 01, attenuated the late rise of the brain temperature, but had no effe ct on the early rise, whereas i.c.v. pretreatment with a competitive N MDA receptor antagonist, (+/-)-2-amino-5-phosphonopentanoic acid (AP-5 ), attenuated both rises. AP-5 per se caused a rise in brain temperatu re without any rise of rectal temperature, whereas MK-801 per se cause d no significant change of the brain or rectal temperature. This rise by AP-5 was suppressed by MK-801, suggesting an agonistic effect of AP -5 on NMDA receptors in rat brain in vivo. (C) 1997 Elsevier Science I nc.