NMDA receptor blockade in the periaqueductal grey prevents stress-induced analgesia in attacked mice.
Microinjections of N-methyl-D-aspartate (NMDA, 0.1 and 1.0 nmol) into the periaqueductal grey (PAG) of the mouse resulted in potential antinociception. In a social conflict situation, attacked mice exhibited a marked analgesia that was prevented by prior injection of the competitive NMDA antagonist, AP-7 (2.0 nmol) or naloxone (6.0 nmol) into the PAG and also by i.p. injection of the non-competitive NMDA antagonist, MK-801 (33 nmol). These results demonstrate that NMDA receptors are involved in endogenous analgesic mechanisms activated by stress.
Siegfried
B
B
Institute of Pharmacology, University of Zurich, Switzerland.
de Souza
R L
RL
D000698:Analgesia; D000818:Animals; D008297:Male; D051379:Mice; D008815:Mice, Inbred Strains; D010487:Periaqueductal Gray / Q000502:physiology* / Q000648:ultrastructure; D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter / Q000037:antagonists & inhibitors*; D011957:Receptors, Opioid / Q000502:physiology; D012919:Social Behavior; D013312:Stress, Physiological / Q000503:physiopathology*
D016194:Receptors, N-Methyl-D-Aspartate; D017981:Receptors, Neurotransmitter; D011957:Receptors, Opioid