The effects of aging on cerebellar beta-adrenergic receptor activation and motor learning in female F344 rats.
Female Fischer 344 (F344) rats were tested for age-related differences in both cerebellar beta-adrenergic receptor activation and motor learning. Three and 20 month old rats were tested on a motor learning paradigm that required the rats to adjust their gait to navigate a runway of unevenly spaced pegs. Rates of acquisition were compared between age groups. After behavioral testing, cerebellar beta-adrenergic receptor function was assessed using extracellular recordings of Purkinje cells during iontophoresis of GABA and isoproterenol (ISO). Aged female rats showed deficits in motor learning and in beta-adrenergic receptor activation. In young rats, ISO modulated GABAergic inhibition of Purkinje cell firing in more cells compared with aged rats. Thus, aging produces deficits in both motor learning and in beta-adrenergic receptor activation in aged female F344 rats.
Department of Pharmacology, University of Colorado Health Sciences Center, Denver 80262, USA.
T J
TJ
Gould
P C
PC
Bickford
D000200:Action Potentials / Q000502:physiology; D000318:Adrenergic beta-Agonists / Q000494:pharmacology*; D000375:Aging / Q000187:drug effects / Q000502:physiology* / Q000523:psychology*; D000818:Animals; D002531:Cerebellum / Q000187:drug effects / Q000254:growth & development / Q000502:physiology*; D005260:Female; D007545:Isoproterenol / Q000494:pharmacology*; D007858:Learning / Q000187:drug effects / Q000502:physiology*; D009048:Motor Skills; D009638:Norepinephrine / Q000097:blood; D011689:Purkinje Cells / Q000502:physiology; D051381:Rats; D011916:Rats, Inbred F344; D005680:gamma-Aminobutyric Acid / Q000494:pharmacology
D000318:Adrenergic beta-Agonists; D005680:gamma-Aminobutyric Acid; D007545:Isoproterenol; D009638:Norepinephrine