Neuropharmacological study of aged MAM-treated rats.
After evaluation of activity in an open field, norepinephrine (NE), serotonin (5HT), 5-hydroxyindolacetic acid (5HIAA), homovanillic acid (HVA), and choline acetyltransferase (CAT) were investigated in cortex of 26-month-old rats poisoned with methylazoxymethanol (MAM) as compared to control rats of the same age. NE and 5HT concentrations showed a marked increase, but levels were normal when expressed as total content, just as in MAM-exposed young adults. Concentrations of 5HIAA were also increased but to a lesser extent than 5 HT. Aged MAM rats did not show any modification of spontaneous activity although hyperactivity is characteristic of young adults exposed to MAM. Together with this behavioral observation, a significant decrease in total HVA content was measured. Because HVA levels seem correlated with activity in MAM-exposed rats, we speculate that the behavioral abnormality recovers in old age. Total CAT activity was also reduced. These results indicate that the neurochemical pattern of young adult MAM-poisoned rats is conserved in aged rats except for some changes in the dopaminergic and cholinergic systems.
Greiner
P O
PO
Institut de Recherche SIR International, Montrouge, France.
Charles
P
P
Bonnet
M
M
Angignard
D
D
Dupont
J M
JM
Herold
M
M
Borzeix
M G
MG
Bonnet
C M
CM
D000375:Aging / Q000378:metabolism / Q000502:physiology*; D000818:Animals; D015306:Biogenic Monoamines / Q000378:metabolism; D001835:Body Weight / Q000187:drug effects; D002540:Cerebral Cortex / Q000187:drug effects / Q000378:metabolism; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D004247:DNA / Q000096:biosynthesis; D005260:Female; D008746:Methylazoxymethanol Acetate / Q000494:pharmacology*; D009419:Nerve Tissue Proteins / Q000378:metabolism; D009929:Organ Size / Q000187:drug effects; D011247:Pregnancy; D051381:Rats; D011919:Rats, Inbred Strains; D013569:Synapses / Q000187:drug effects / Q000378:metabolism
D015306:Biogenic Monoamines; D009419:Nerve Tissue Proteins; D008746:Methylazoxymethanol Acetate; D004247:DNA; D002795:Choline O-Acetyltransferase