Pharmacological models of ADHD.
R M Kostrzewa1, J P Kostrzewa, R A Kostrzewa
1Department of Pharmacology, Quillen College of Medicine, East Tennessee State University, Johnson City, TN 37614, USA. kostrzew@etsu.edu
Journal of Neural Transmission (Vienna, Austria : 1996)
|November 13, 2007
Summary
Various exposures can cause hyperactivity in rodents, modeling attention deficit hyperactivity disorder (ADHD). Research explores the neurobiological underpinnings of ADHD, focusing on dopaminergic systems.
Area of Science:
- Neuroscience
- Pharmacology
- Developmental Biology
Background:
- Long-term hyperactivity in rodents is linked to early-life exposure to heavy metals, hypoxia, X-rays, methylazoxymethanol, polychlorinated biphenyls (PCBs), and nicotine.
- These models are used to study attention deficit hyperactivity disorder (ADHD), though its exact cause in children remains unclear.
- Neonatal 6-hydroxydopamine (6-OHDA) induced dopaminergic denervation is a widely used animal model for ADHD.
Purpose of the Study:
- To review pharmacological models of attention deficit hyperactivity disorder (ADHD).
- To associate specific brain regions and neuronal phenotypes with ADHD-related behavioral dysfunctions.
Main Methods:
- Review of established animal models for attention deficit hyperactivity disorder (ADHD).
- Analysis of the effects of amphetamine (AMPH) and methylphenidate (MPH) in these models.
- Examination of genetic models and monoaminergic system involvement.
Main Results:
- Rodent models demonstrate hyperactivity and attention deficits following various developmental insults.
- Standard ADHD medications like amphetamine (AMPH) and methylphenidate (MPH) often ameliorate these symptoms.
- Monoaminergic systems, particularly dopaminergic, noradrenergic, and serotoninergic pathways in the forebrain, are implicated in ADHD.
Conclusions:
- Pharmacological models provide insights into the neurobiology of attention deficit hyperactivity disorder (ADHD).
- Specific forebrain monoaminergic systems are strongly associated with ADHD-like behaviors.
- Further research is needed to fully elucidate the neuronal basis of childhood hyperactivity and attention deficits.
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