Nj. Desousa et al., Self administration of intravenous amphetamine is predicted by individual differences in sucrose feeding in rats, PSYCHOPHAR, 148(1), 2000, pp. 52-58
Rationale: Previous studies have shown that individual differences in oral
sucrose consumption are predictive of the psychomotor and dopamine (DA) sti
mulant properties of amphetamine in rats. Objectives: The present experimen
t was designed to examine the relationship between sucrose feeding and the
reinforcing properties of amphetamine using the intravenous (i.v.) drug sel
f-administration paradigm, Methods: Based on a median split of sucrose inta
ke during a final 1-h feeding test session, male Wistar rats were designate
d as either low (LSF) or high sucrose feeders (HSE). Acquisition of i.v.-am
phetamine self-administration across ten daily 30-min sessions was then ass
essed. Following acquisition, i.v. self-administration of several doses of
amphetamine was similarly tested across daily 30-min sessions. Results: Dat
a from this experiment revealed augmented responding in HSF compared with L
SF during acquisition of amphetamine self-administration. Correspondingly,
when given access to different doses of amphetamine, responding was greater
in HSF than in LSF across several doses (3 mu g and 10 mu g per infusion).
Conclusions: These data support the notion that individual differences in
oral sucrose consumption are predictive of the reinforcing properties of ps
ychostimulant drugs.