Previous studies investigating adaptations following cocaine self-administration have shown that the development of reduced cocaine potency at the dopamine transporter (DAT) results from high, continuous levels of intake (long access, LgA), whereas sensitization of cocaine potency is caused by intermittent patterns of cocaine administration (intermittent access, IntA). Here we determined whether the changes observed following cocaine self-administration were specific to cocaine or translated to other psychostimulants. We assessed the potency of amphetamine, a releaser, and methylphenidate (MPH), a DAT blocker that is functionally similar to cocaine and structurally related to amphetamine. MPH and amphetamine potencies were increased following IntA, whereas neither was changed following LgA. This demonstrates that the pattern with which cocaine is administered determines the neurochemical consequences of cocaine and the sensitization of other psychostimulants.
See article at J Pharmacol Exp Ther 2014, 349:192–198.
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