Decline in motor functions in aging is related to the loss of NMDA receptors.
The aim of the study was to assess the contribution of central dopaminergic and glutamatergic systems to the age-dependent loss of motor functions in rats. Rats of three age groups were compared: young (3-5-month-old), middle-aged (20-21-month-old) and old (29-31-month-old). The obtained results showed an age-dependent decline in the electromyographic (EMG) resting and reflex activities in the gastrocnemius and tibialis anterior muscles, as well as in the T-maze performance. Although these disturbances were accompanied with significant age-dependent decreases in the binding to NMDA, AMPA and dopamine D2 receptors, and a decline in the number of nigral dopamine neurons, they were significantly correlated with the loss of the binding to NMDA receptors only. The reduction in T-maze performance with aging was additionally correlated with a decrease in motor functions (EMG activity). The study suggests a crucial role of the loss of NMDA receptors in age-dependent motor disabilities, as well as in disturbances measured in the T-maze.
Ossowska
K
K
Department of Neuro-Psychopharmacology, Institute of Pharmacology, Polish Academy of Sciences, 12 Smetna St., 31-343, Kraków, Poland. ossowska@if-pan.krakow.pl
Wolfarth
S
S
Schulze
G
G
Wardas
J
J
Pietraszek
M
M
Lorenc-Koci
E
E
Smiałowska
M
M
Coper
H
H
D000375:Aging / Q000378:metabolism* / Q000523:psychology; D000818:Animals; D000843:Ankle Joint / Q000503:physiopathology; D015415:Biomarkers; D001696:Biomechanical Phenomena; D001931:Brain Mapping; D002452:Cell Count; D016291:Dizocilpine Maleate / Q000378:metabolism; D004298:Dopamine / Q000502:physiology*; D004576:Electromyography; D005260:Female; D018698:Glutamic Acid / Q000502:physiology*; D007859:Learning Disabilities / Q000209:etiology / Q000378:metabolism / Q000473:pathology; D018782:Maze Learning; D009069:Movement Disorders / Q000209:etiology* / Q000378:metabolism / Q000473:pathology; D018482:Muscle, Skeletal / Q000378:metabolism / Q000503:physiopathology; D009419:Nerve Tissue Proteins / Q000032:analysis* / Q000502:physiology; D018583:Pliability; D011597:Psychomotor Performance; D020891:Raclopride / Q000378:metabolism; D051381:Rats; D017208:Rats, Wistar; D011930:Reaction Time; D018091:Receptors, AMPA / Q000032:analysis / Q000378:metabolism; D017448:Receptors, Dopamine D2 / Q000032:analysis / Q000378:metabolism; D016194:Receptors, N-Methyl-D-Aspartate / Q000032:analysis* / Q000378:metabolism / Q000502:physiology; D013378:Substantia Nigra / Q000378:metabolism / Q000473:pathology; D014446:Tyrosine 3-Monooxygenase / Q000032:analysis; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid / Q000378:metabolism
D015415:Biomarkers; D009419:Nerve Tissue Proteins; D018091:Receptors, AMPA; D017448:Receptors, Dopamine D2; D016194:Receptors, N-Methyl-D-Aspartate; D018698:Glutamic Acid; D020891:Raclopride; D016291:Dizocilpine Maleate; D018350:alpha-Amino-3-hydroxy-5-methyl-4-isoxazolepropionic Acid; D014446:Tyrosine 3-Monooxygenase; D004298:Dopamine