Linked Life Data

16621932

Source:http://linkedlifedata.com/resource/pubmed/id/16621932

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
7
pubmed:dateCreated
2006-6-22
pubmed:abstractText
The psychostimulant medications methylphenidate (MPH) and amphetamine (AMP), available in various ratios or enantiopure formulations of their respective active dextrorotary isomers, constitute the majority of agents used in the treatment of attention-deficit/hyperactivity disorder (ADHD). Substantial interindividual variability occurs in their pharmacokinetics and tolerability. Little is known regarding the potential role of drug transporters such as P-glycoprotein (P-gp) in psychostimulant pharmacokinetics and response. Therefore, experiments were carried out in P-gp knockout (KO) mice versus wild-type (WT) mice after intraperitoneal dosing (2.5 mg/kg) of d-MPH or (3.0 mg/kg) of d-AMP. After the administration of each psychostimulant, locomotor activity was assessed at 30-min intervals for 2 h. Total brain-to-plasma drug concentration ratios were determined at 10-, 30-, and 80-min postdosing time-points. The results showed no statistically supported genotypic difference in d-AMP-induced locomotor activity stimulation or in brain-to-plasma ratio of d-AMP. As for d-MPH, the P-gp KO mice had 33% higher brain concentrations (p < 0.05) and 67.5% higher brain-to-plasma ratios (p < 0.01) than WT controls at the 10-min postdosing timepoint. However, in spite of elevated brain concentrations, d-MPH-induced locomotor activity increase was attenuated for P-gp compared with that for WT mice. These data indicate that P-gp has no apparent effect on the pharmacokinetics and pharmacodynamics of d-AMP. In addition, d-MPH is a relatively weak P-gp substrate, and its entry into the brain may be limited by P-gp. Furthermore, the mechanism by which d-MPH-induced locomotor activity was attenuated in P-gp KO mice remains to be elucidated.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jul
pubmed:issn
0090-9556
pubmed:author
pubmed:issnType
Print
pubmed:volume
34
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1116-21
pubmed:dateRevised
2011-6-21
pubmed:meshHeading
pubmed:year
2006
pubmed:articleTitle
The role of the polymorphic efflux transporter P-glycoprotein on the brain accumulation of d-methylphenidate and d-amphetamine.
pubmed:affiliation
Department of Pharmaceutical Sciences, Medical University of South Carolina, Charleston, SC 29425, USA.
pubmed:publicationType
Journal Article, Comparative Study, Research Support, N.I.H., Extramural