N-methyl-D-aspartate receptor binding in brains of rats at different ages.
Potential age differences in N-methyl-D-aspartate (NMDA) receptor binding were evaluated in rat brain using [3H]dizocilpine and [3H]D,L-(E)-2-amino-4-propyl-5-phosphono-3-pentanoic acid (CGP 39653) as the radioligands. Neither [3H]dizocilpine nor [3H]CGP 39653 binding in hippocampus revealed any age difference (7 vs. 23-25 months) in Bmax or Kd. High-affinity [3H]dizocilpine binding showed a developmental increase (8 vs. 2 months) in hippocampus but not in frontal cortex. No senescence-related change (25 vs. 8 months) was observed in either region. The lack of senescence-related differences in these biochemical markers does not preclude the possibility of functional changes in the NMDA receptor with aging.
Shimada
A
A
Molecular Physiology and Genetics Section, National InstitUte on Aging, National Institutes of Health, Baltimore, MD 21224, USA.
Mukhin
A
A
Ingram
D K
DK
London
E D
ED
D015763:2-Amino-5-phosphonovalerate / Q000031:analogs & derivatives / Q000494:pharmacology; D000375:Aging / Q000378:metabolism*; D000818:Animals; D001921:Brain / Q000378:metabolism*; D016291:Dizocilpine Maleate / Q000494:pharmacology; D018691:Excitatory Amino Acid Antagonists / Q000494:pharmacology; D008297:Male; D011869:Radioligand Assay; D051381:Rats; D011916:Rats, Inbred F344; D016194:Receptors, N-Methyl-D-Aspartate / Q000378:metabolism*
D018691:Excitatory Amino Acid Antagonists; D016194:Receptors, N-Methyl-D-Aspartate; C069052:CGP 39653; D016291:Dizocilpine Maleate; D015763:2-Amino-5-phosphonovalerate