Dataset Information

Differences in methylphenidate dose response between periadolescent and adult rats in the familiar arena-novel alcove task.

ABSTRACT: Methylphenidate is a psychostimulant widely used in the treatment of attention deficit hyperactivity disorder. In this study, the effects of two nonstereotypy-inducing doses of methylphenidate (2.5 and 5.0 mg/kg s.c.) were examined in periadolescent [postnatal days (P) 35 and 42] and young adult (P70), male Long-Evans rats using a three-period locomotor activity paradigm that affords inferences about exploration, habituation, and attention to a novel stimulus (an "alcove") in a familiar environment in a single test session. In the first test period, P35 and P42 rats were more active than P70 rats, and methylphenidate increased locomotion in a dose-related manner. The introduction of a novel spatial stimulus in the third test period revealed a significant interaction of dose and age such that P70 rats exhibited dose-related increases in distance traveled, but P35 rats did not. Furthermore, methylphenidate dose-relatedly disrupted the rats' tendency to spend increasing amounts of time in the alcove across the test period at P70 but not at P35. Brain and serum methylphenidate concentrations were significantly lower at P35 than at P70, with intermediate levels at P42. Developmental differences in dopaminergic neurochemistry were also observed, including increased dopamine content in the caudate-putamen, nucleus accumbens, and frontal cortex and decreased densities of D(1)-like receptors in the frontal cortex in P70 than in P42 rats. These results raise the possibility that children and adults may respond differently when treated with this drug, particularly in situations involving response to novelty and that these effects involve developmental differences in pharmacokinetics and dopaminergic neurochemistry.

SUBMITTER: Levant B

PROVIDER: S-EPMC3063734 | biostudies-literature | 2011 Apr

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Differences in methylphenidate dose response between periadolescent and adult rats in the familiar arena-novel alcove task.

Levant Beth B Zarcone Troy J TJ Davis Paul F PF Ozias Marlies K MK Fowler Stephen C SC

The Journal of pharmacology and experimental therapeutics 20101228 1

Methylphenidate is a psychostimulant widely used in the treatment of attention deficit hyperactivity disorder. In this study, the effects of two nonstereotypy-inducing doses of methylphenidate (2.5 and 5.0 mg/kg s.c.) were examined in periadolescent [postnatal days (P) 35 and 42] and young adult (P70), male Long-Evans rats using a three-period locomotor activity paradigm that affords inferences about exploration, habituation, and attention to a novel stimulus (an "alcove") in a familiar environm ...[more]

PMID: 21205916

Similar Datasets

Project description:BackgroundAdolescents and adults vary in sensitivity to many effects of ethanol (EtOH), although it is unknown whether they also differ in their perception of EtOH's subjective cues. This study characterized EtOH discrimination in adolescent and adult male rats using a rapidly acquired Pavlovian conditioned approach procedure.MethodsEtOH at 1 of the 3 training doses (0.75, 1.0, or 1.25 g/kg) served as either a positive (POS) or negative (NOS) occasion setter. Each 20-minute training session consisted of eight 15-second presentations of 2 cue lights located on either side of a dipper delivering chocolate Boost(®) . For POS-trained rats, the cue lights reliably predicted 5-second presentations of chocolate Boost during EtOH but not saline sessions, with the opposite contingencies used for NOS-trained rats. Anticipatory approach behavior (head entries into the reward delivery area) in the presence and absence of the cue lights was used to calculate discrimination scores on EtOH and saline sessions. Following acquisition, various doses of EtOH (0 to 1.5 g/kg) were administered to establish generalization curves.ResultsAlthough animals of both ages responded differentially on EtOH and saline sessions by the end of acquisition, adults met criterion more quickly and had higher discrimination scores during reinforced sessions than adolescents. Whereas adolescents failed to demonstrate any dose-dependent responding during testing when trained with the 0.75 or 1.25 g/kg EtOH doses, adults demonstrated broader EtOH generalization during testing sessions following training with all 3 EtOH doses. Among adolescents trained with 1.0 g/kg EtOH, less generalization occurred relative to adults.ConclusionsAdolescents were less sensitive to EtOH's interoceptive effects, indicating that EtOH is likely a more salient cue for adults than for adolescents. These findings contribute to evidence that suggests adolescent-typical insensitivity to internal cues that typically limit EtOH consumption may contribute to the elevated intake commonly reported during this developmental period.

Dataset Information

Differences in methylphenidate dose response between periadolescent and adult rats in the familiar arena-novel alcove task.

Publications

Differences in methylphenidate dose response between periadolescent and adult rats in the familiar arena-novel alcove task.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets