RT Journal Article
SR Electronic
T1 A Single Exposure to Amphetamine Is Sufficient to Induce Long-Term Behavioral, Neuroendocrine, and Neurochemical Sensitization in Rats
JF The Journal of Neuroscience
JO J. Neurosci.
FD Society for Neuroscience
SP 9579
OP 9586
DO 10.1523/JNEUROSCI.19-21-09579.1999
VO 19
IS 21
A1 Louk J. M. J. Vanderschuren
A1 E. Donné Schmidt
A1 Taco J. De Vries
A1 Caroline A. P. Van Moorsel
A1 Fred J.H. Tilders
A1 Anton N. M. Schoffelmeer
YR 1999
UL http://www.jneurosci.org/content/19/21/9579.abstract
AB Repeated treatment with psychostimulant drugs causes long-lasting behavioral sensitization and associated neuroadaptations. Although sensitization induced by a single psychostimulant exposure has also been reported, information on the behavioral and neurochemical consequences of a single psychostimulant exposure is sparse. Therefore, to evaluate whether behavioral sensitization evoked by single and repeated psychostimulant pretreatment regimens represent the same neurobiological phenomenon, the time-dependent expression of behavioral, neurochemical, and neuroendocrine sensitization after a single exposure to amphetamine was investigated in rats. A single exposure to amphetamine (5 mg/kg, i.p.) caused context-independent sensitization of the locomotor effects of amphetamine, which intensified over time. Thus, sensitization to amphetamine was marginal at 3 d after treatment and more evident after 1 week, whereas 3 weeks after treatment, profound sensitization, as well as cross-sensitization, to cocaine was observed. Amphetamine pretreatment caused an increase in the electrically evoked release of [3H]dopamine from nucleus accumbens, caudate putamen, and medial prefrontal cortex slices and of [14C]acetylcholine from accumbens and caudate slices. The hyperreactivity of dopaminergic nerve terminals appeared to parallel the development of locomotor sensitization, i.e., whereas hyperreactivity of accumbens dopaminergic terminals increased between 3 d and 3 weeks after treatment, the hyperreactivity of medial prefrontal dopaminergic terminals decreased. Pre-exposure to amphetamine also sensitized the hypothalamus–pituitary–adrenal axis response to amphetamine at 1 and 3 weeks, but not at 3 d after treatment. Because these data closely resemble those reported previously for repeated amphetamine pretreatment, it is concluded that a single exposure to amphetamine is sufficient to induce long-term behavioral, neurochemical, and neuroendocrine sensitization in rats.