Apomorphine effects on episodic memory in young healthy volunteers.
BACKGROUND
Dopamine (DA) modulates working memory. However, the relation between DA systems and episodic (declarative) memory is less established. Frontal lobe DA function may be involved. We were interested in assessing whether apomorphine (Apo), a drug used extensively in clinical research as a probe of DA function, has an effect on episodic memory test performance in healthy volunteers.


OBJECTIVE
To investigate the effect of a presynaptic dose of Apo on episodic memory tests and on other tests thought to be sensitive to frontal lobe functions.


METHODS
Twenty healthy subjects were treated with Apo HCl (5 microg/kg sc) or placebo (10 subjects/group) in a randomized, double blind parallel group design and performance on a battery of cognitive tests was assessed.


RESULTS
Apomorphine significantly impaired performance on tests of source recognition (d.f.=19, p=0.05) and item recognition memory (d.f.=19, p<0.05), and memory interference (d.f.=19, p<0.010). No significant change was found on other tests (Go/no-Go Test, Categorized Words, Stroop, Trail Making Test, and verbal fluency).


CONCLUSIONS
Findings in this small sample of subjects suggest that dopaminergic transmission affects episodic memory functions.
Montoya
Alonso
A
Douglas Mental Health University Institute, Department of Psychiatry, McGill University, Verdun, Quebec, Canada.
Lal
Samarthji
S
Menear
Matthew
M
Duplessis
Elisabeth
E
Thavundayil
Joseph
J
Schmitz
Norbert
N
Lepage
Martin
M
D000161:Acoustic Stimulation; D000328:Adult; D001058:Apomorphine / Q000494:pharmacology*; D018491:Dopamine Agonists / Q000494:pharmacology*; D004311:Double-Blind Method; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects*; D009483:Neuropsychological Tests; D014706:Verbal Learning / Q000187:drug effects
D018491:Dopamine Agonists; D001058:Apomorphine