[Age related alterations of motor behavior and release of dopaminergic supersensitivity in rats].
Rats aged greater than or equal to 18 months show, aside from clearly diminished motor parameters (exploratory behavior, resting activity, nocturnal activity profile, rotation behavior), after intracerebral dopamine injection a considerably lower apomorphine hypermotility than young animals. The characteristic alteration of activity occurring in young rats during and following chronic administration of haloperidol (1 mg/kg . day, s.c. for 21 days) as an expression of developing dopaminergic supersensitivity does not appear in older animals. Repeated application of amphetamine (2 X 2 mg/kg daily) caused a significant increase in hypermotility. The results are interpreted as the consequence of a age-related reduction of the activity of central-dopaminergic transmission systems and are discussed with regard to possible differences in the realization of agonist- or antagonist-induced supersensitivity.
D000367:Age Factors; D000661:Amphetamine / Q000494:pharmacology; D000818:Animals; D004298:Dopamine / Q000494:pharmacology*; D004342:Drug Hypersensitivity / Q000378:metabolism*; D006220:Haloperidol / Q000494:pharmacology; D008297:Male; D009043:Motor Activity / Q000187:drug effects*; D051381:Rats; D011919:Rats, Inbred Strains; D009435:Synaptic Transmission / Q000187:drug effects
D000661:Amphetamine; D006220:Haloperidol; D004298:Dopamine
Altersbedingte Veränderungen des motorischen Verhaltens und der Auslösbarkeit der dopaminergen Supersensitivität bei Ratten.