Related Experiment Video

Updated: Aug 11, 2026

Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids
07:26

Metabolic Pathway Confirmation and Discovery Through 13C-labeling of Proteinogenic Amino Acids

Published on: January 26, 2012

Derivatization and mass spectrometric behaviour of catecholamines and their 3-O-methylated metabolites

A C Tas, J Odink, M C ten Noever de Brauw

    Journal of Chromatography
    |October 12, 1984
    PubMed

    More Related Videos

    Integration of Miniaturized Solid Phase Extraction and LC-MS/MS Detection of 3-Nitrotyrosine in Human Urine for Clinical Applications08:41

    Integration of Miniaturized Solid Phase Extraction and LC-MS/MS Detection of 3-Nitrotyrosine in Human Urine for Clinical Applications

    Published on: July 14, 2017

    A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites13:35

    A Convenient Method for Extraction and Analysis with High-Pressure Liquid Chromatography of Catecholamine Neurotransmitters and Their Metabolites

    Published on: March 1, 2018

    Related Concept Videos

    NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones01:15

    NMR Spectroscopy and Mass Spectrometry of Aldehydes and Ketones

    In aldehydes, the hydrogen atom connected to the carbonyl carbon helps distinguish aldehydes from other carbonyl compounds using ¹H NMR spectroscopy. The closeness of aldehydic hydrogen to the electrophilic carbonyl carbon highly deshields the hydrogen atom causing its signal to appear around 10 ppm in the ¹H NMR spectra. α hydrogens split the aldehydic proton signal, which helps identify the number of α hydrogens in the molecule. For instance, one α hydrogen creates a doublet for an aldehydic...
    Mass Spectrometry: Aldehyde and Ketone Fragmentation01:09

    Mass Spectrometry: Aldehyde and Ketone Fragmentation

    In mass spectrometry, the fragmentation of aliphatic aldehydes and ketones generally occurs through three key mechanisms: α-cleavage, inductive cleavage, and the McLafferty rearrangement.
    Adrenergic Neurons: Neurotransmission01:27

    Adrenergic Neurons: Neurotransmission

    Postganglionic sympathetic fibers (except those supplying the sweat glands) releasing noradrenaline or norepinephrine are called noradrenergic or adrenergic neurons. Noradrenaline, dopamine, adrenaline, or epinephrine are collectively called "catecholamines" as they contain a catechol moiety and an amine side chain. The five stages of neurotransmitter release involve their synthesis, storage, release, reuptake and metabolism.
    Synthesis: Catecholamine synthesis requires tyrosine, which is taken...
    Adrenergic Agonists: Indirect-Acting Agents01:25

    Adrenergic 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...
    Adrenergic Agonists: Chemistry and Structure-Activity Relationship01:16

    Adrenergic Agonists: Chemistry and Structure-Activity Relationship

    Adrenergic agonists' structure-activity relationship (SAR) determines their selectivity and efficacy. These agonists comprise a phenylethylamine moiety with an aromatic ring and an ethylamine side chain.
    Aromatic ring substitutions: Substituting the aromatic ring with –OH groups at positions 3 and 4 yields catecholamines (e.g., epinephrine), which have a high affinity for adrenoceptors. Hydrogen bonding between –OH groups and receptors enhances adrenergic activity.
    Separation of the aromatic...
    Phase II Reactions: Methylation Reactions01:17

    Phase II Reactions: Methylation Reactions

    Methylation is a phase II biotransformation process involving the attachment of a methyl group to a substrate. Enzymes known as methyltransferases orchestrate this reaction.
    The mechanism of methylation unfolds in two stages. The first stage sees a methyltransferase enzyme facilitating the transfer of a methyl group from S-adenosylmethionine (SAM) to the substrate, forming S-adenosylhomocysteine (SAH). The second stage involves further metabolism of SAH into homocysteine, which can be recycled...