Related Experiment Video
Updated: Aug 17, 2026
07:30
Single Cell Measurement of Dopamine Release with Simultaneous Voltage-clamp and Amperometry
Published on: November 21, 2012
Dopamine-norepinephrine interaction in hyperactive boys treated with d-amphetamine
The Journal of Pediatrics
|May 1, 1982
Summary
This study found that the relationship between norepinephrine and dopamine metabolites differs in hyperactive boys compared to controls. D-amphetamine treatment normalized this relationship in hyperactive children.
Area of Science:
- Neuroscience
- Biochemistry
- Pediatrics
Background:
- Hyperactivity in children is linked to neurotransmitter imbalances.
- Norepinephrine (NE) and Dopamine (DA) are key central nervous system neurotransmitters.
- Urinary metabolites 3-methoxy-4-hydroxyphenylglycol (MHPG) and homovanillic acid (HVA) reflect NE and DA activity, respectively.
Purpose of the Study:
- To investigate the relationship between MHPG and HVA excretion in hyperactive boys versus controls.
- To examine the effect of d-amphetamine on this relationship.
- To explore potential alterations in central NE and DA activity in childhood hyperactivity.
Main Methods:
- Measured urinary MHPG and HVA excretion in 16 hyperactive boys and 10 controls.
- Administered d-amphetamine (0.5 mg/kg/day for two weeks) to participants.
- Analyzed correlations between MHPG and HVA, controlling for age, body surface, and urinary creatinine.
Main Results:
- A significant negative correlation between MHPG and HVA was found in hyperactive boys, contrasting with a positive correlation in controls.
- Baseline correlations in hyperactive boys and responders differed significantly from post-treatment values.
- Post-treatment correlations in hyperactive boys matched those of controls.
Conclusions:
- Suggests an altered relationship between dopamine and norepinephrine activity in hyperactive children.
- D-amphetamine treatment appears to normalize the NE-DA metabolic relationship in hyperactive individuals.
- Further research is needed to fully elucidate the contribution of central neurotransmitter metabolism to urinary MHPG and HVA levels.
More Related Videos
11:26Assessment of Dopaminergic Homeostasis in Mice by Use of High-performance Liquid Chromatography Analysis and Synaptosomal Dopamine Uptake
Published on: September 21, 2017
10:02Event Related Potentials (ERPs) and other EEG Based Methods for Extracting Biomarkers of Brain Dysfunction: Examples from Pediatric Attention Deficit/Hyperactivity Disorder (ADHD)
Published on: March 12, 2020
Related Concept Videos
01:23Drugs Acting on Autonomic Ganglia: Stimulants
Ganglionic stimulants activate NM nicotinic receptors in autonomic ganglia, falling into two categories: nicotine mimetics [e.g., lobeline, dimethylpiperazine, tetramethylammonium] and muscarinic receptor agonists [e.g., muscarine, methacholine]. The first category's action is rapid and blocked by nicotinic receptor antagonists, while the second category's action is delayed and blocked by atropine-like agents. Nicotine, an alkaloid, affects the heart rate by stimulating sympathetic or...
01:25Adrenergic Agonists: Indirect-Acting Agents
Indirect-acting adrenergic agonists potentiate the effects of endogenous catecholamines through different mechanisms without directly binding to adrenoceptors.
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
One mechanism involves depleting stored catecholamines by displacing them from synaptic vesicles. These agents, known as "displacers," are transported into vesicles at the expense of noradrenaline. Examples include amphetamine and tyramine, which lack a catechol moiety, resulting in prolonged action, improved oral bioavailability, and...
01:28Adrenergic Agonists: Mixed-Action Agents
Mixed-action adrenergic agonists, like ephedrine and pseudoephedrine, directly and indirectly affect adrenergic receptors. These agents stimulate adrenoceptors and indirectly release stored neurotransmitters, amplifying the adrenergic response.
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
Ephedrine and pseudoephedrine lack a catecholamine group, making them less susceptible to degradation by metabolic enzymes. They have increased oral bioavailability and lipophilicity, resulting in a longer duration of action. Their response is reduced by...
01:29Drugs Affecting Neurotransmitter Synthesis
Drugs affecting neurotransmitter synthesis can impact the adrenergic neuron and the synthesis of neurotransmitters. For example, α-methyltyrosine and carbidopa target specific enzymes involved in catecholamine synthesis. α-methyltyrosine inhibits the enzyme tyrosine hydroxylase, which converts tyrosine into dopamine. By blocking this enzyme, α-methyltyrosine reduces dopamine production and other catecholamines. Carbidopa, on the other hand, inhibits the enzyme dopa decarboxylase, which converts...
01:24CNS Stimulants: Cocaine, Amphetamines and Cannabinoids
CNS stimulants, such as cocaine, amphetamines, and cannabinoids, have varying structures and mechanisms of action that lead to different therapeutic effects and side effects. Cocaine, with its molecular formula C17H21NO4, is a tropane alkaloid and a tertiary amino compound. It has two chemical forms: the hydrochloride salt and the "freebase." The former is in powder form, while the latter involves removing the hydrochloride salt to create a form that can be smoked. Cocaine exerts its effects by...
01:30Attention-Deficit/Hyperactivity Disorder
Attention-deficit/hyperactivity disorder (ADHD) is a neurodevelopmental disorder characterized by persistent inattention, hyperactivity, and impulsivity. It affects approximately 5-8% of children globally, with around 60-70% of cases persisting into adulthood. ADHD has significant implications for educational attainment, social interactions, and occupational success.
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings.
Diagnostic Criteria and Symptoms
To diagnose ADHD, symptoms must manifest before age 12 and be evident across multiple settings.