Related Experiment Video

Updated: Mar 30, 2026

Preparation of Gynura bicolor DC samples for High-Resolution Tandem Mass Spectrometry
07:16

Preparation of Gynura bicolor DC samples for High-Resolution Tandem Mass Spectrometry

Published on: February 2, 2024

1.1K

[Studies on chemical constituents from Psychotria straminea]

Yan-hui Fu, Li-gang Huang, Xiao-cui Wang

    Zhongguo Zhong Yao Za Zhi = Zhongguo Zhongyao Zazhi = China Journal of Chinese Materia Medica
    |November 11, 2015
    PubMed

    More Related Videos

    Author Spotlight: Discovering New Alkaloids in Plants with Advanced Mass Spectrometry Techniques09:36

    Author Spotlight: Discovering New Alkaloids in Plants with Advanced Mass Spectrometry Techniques

    Published on: March 8, 2024

    1.6K
    Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry11:14

    Rapid High-throughput Species Identification of Botanical Material Using Direct Analysis in Real Time High Resolution Mass Spectrometry

    Published on: October 2, 2016

    12.2K

    Related Concept Videos

    Cholinergic Antagonists: Chemistry and Structure-Activity Relationship01:29

    Cholinergic Antagonists: Chemistry and Structure-Activity Relationship

    Cholinergic antagonists bind to cholinergic receptors and limit the effects of acetylcholine and other cholinergic agonists. Based on the specific cholinergic receptor affinity, these antagonists are classified as muscarinic or nicotinic. Anticholinergics interrupt parasympathetic innervations while sympathetic innervations remain uninterrupted. Muscarinic antagonists are also called 'muscarinic antagonists', 'antimuscarinics', or 'parasympatholytics'. Nicotinic...
    3.0K
    Spasmolytic Agents: Chemical Classification01:29

    Spasmolytic Agents: Chemical Classification

    Spasmolytic agents are drugs used to alleviate muscle spasms and spasticity. They can be categorized into different chemical groups based on their mechanisms of action. Centrally acting spasmolytics primarily affect the spinal cord, while others directly target skeletal muscle cells.
    A major class of centrally acting spasmolytics is the α2-agonist, such as tizanidine. These drugs bind to α2-adrenoceptors, inhibiting the release of the excitatory neurotransmitter glutamate. They also...
    1.4K
    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...
    4.1K
    Direct-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship01:22

    Direct-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship

    Cholinergic agonists or cholinomimetics mimic the action of acetylcholine to stimulate the parasympathetic nervous system. They are categorized into direct-acting and indirect-acting agents. The direct-acting cholinergic drugs induce the parasympathetic response by directly binding to the muscarinic or nicotine receptors. In comparison, the indirect-acting cholinergic drugs prevent acetylcholine hydrolysis, indirectly contributing to the extended parasympathetic response.
    The direct-acting...
    2.5K
    Drugs Acting on Autonomic Ganglia: Stimulants01:23

    Drugs 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...
    2.3K
    Indirect-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship01:29

    Indirect-Acting Cholinergic Agonists: Chemistry and Structure-Activity Relationship

    Indirect-acting cholinergic agonists are agents that interact with the acetylcholinesterase enzyme in the synaptic cleft, preventing the breakdown of acetylcholine into choline and acetate. Consequently, the concentration of acetylcholine in the synaptic cleft increases. These agonists can be classified into reversible and irreversible inhibitors based on their duration of action.
    Reversible inhibitors display short to medium durations of action. Short-acting agents include simple alcohols with...
    1.1K