A cluster analysis study of acetyl-L-carnitine effect on NMDA receptors in aging.
Aging is associated with a reduction in the maximum density of n-methyl-d-aspartate (NMDA)-sensitive glutamate binding sites in the hippocampus of Fischer 344 rats. This study was designed to investigate the effect of acetyl-l-carnitine (ALCAR) on NMDA receptors in the old rat (24 months) after chronic or single-dose treatments. The number of NMDA receptors was significantly decreased in the old rat hippocampus by 19.5% compared with the young rat. A six-month treatment with ALCAR in the old rat attenuated the loss of NMDA binding sites in the hippocampus. A single-dose treatment with ALCAR in the old rat increased the Bmax value by 35%, while no change was observed in the young group. We conclude that ALCAR can exert two actions: a trophic/neuro-preserving one when chronically administered during aging, and a stimulatory one when given at a single dose in the aged rat.
Castorina
M
M
Institute for Research on Senescence, Sigma Tau S.p.A., Rome, Italy.
Ambrosini
A M
AM
Giuliani
A
A
Pacifici
L
L
Ramacci
M T
MT
Angelucci
L
L
D000108:Acetylcarnitine / Q000494:pharmacology*; D000375:Aging / Q000378:metabolism*; D000818:Animals; D016000:Cluster Analysis; D008297:Male; D051381:Rats; D011916:Rats, Inbred F344; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis / Q000187:drug effects*
D016194:Receptors, N-Methyl-D-Aspartate; D000108:Acetylcarnitine