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We have previously shown that 1 h, but not 6 h, of daily access to IV cocaine induces a sensitized response to IV cocaine challenge after 14 days of withdrawal. Here we tried to replicate these results using an IP cocaine challenge and adding a group of animals that had 1 h daily access to cocaine, but maintained levels of administration comparable to that of saline animals (i.e. a Coc group). Since addiction-associated neuroadaptations are particularly long lasting, we also tested the response to cocaine challenge after a longer withdrawal period of 60 days. Rats had daily access to IV self-administered saline or cocaine for 1 h (Coc1h), or to cocaine for 6 h (Coc6h) over 8 days. Subsequently, after 14 days of withdrawal only Coc animals showed a sensitized locomotor response to cocaine challenge administered IP. After 60 days of withdrawal, IP cocaine failed to produce a sensitized response in Coc1h animals …