The effects of N-methyl-D-aspartate (NMDA) and non-NMDA receptor agonists and antagonists on hypothalamic neurones in the anaesthetized rat which respond to changes in scrotal skin temperature.
There are neurones in the pre-optic anterior hypothalamus of the anaesthetised rat which respond to changes in scrotal skin temperature. Neuronal firing rate can be increased by raising the scrotal skin temperature above 36 degrees C, and also by ionophoretic application of either N-methyl-D-aspartate (NMDA) or alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) (a non-NMDA receptor agonist). The increase in neuronal firing evoked by thermal stimulation was prevented or diminished by concurrent application of either D-2-amino-5-phosphonopentanoic acid (D-AP5) (an NMDA receptor antagonist) or 2,3-dihydroxy-6-nitro-7-sulfamoyl-benzo(F)quinoxaline (a non-NMDA receptor antagonist) at doses which were sufficient to abolish or significantly diminish the effect of the specific agonist. It is probable that both NMDA and non-NMDA receptors are involved in the scrotal thermoafferent pathway in the rat.
Taylor
D C
DC
Physiological Laboratory, University of Liverpool, UK. dcmt@liverpool.ac.uk
Gayton
R J
RJ
Miley
H E
HE
Cross
N P
NP
Parton
M P
MP
D000344:Afferent Pathways / Q000378:metabolism; D000818:Animals; D007031:Hypothalamus / Q000187:drug effects*; D008297:Male; D016202:N-Methylaspartate / Q000494:pharmacology*; D051381:Rats; D017207:Rats, Sprague-Dawley; D016194:Receptors, N-Methyl-D-Aspartate / Q000187:drug effects*; D013696:Temperature; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000494:pharmacology*
D016194:Receptors, N-Methyl-D-Aspartate; D016202:N-Methylaspartate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid