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Detection of Toxin Translocation into the Host Cytosol by Surface Plasmon Resonance
Published on: January 3, 2012
Brevetoxin derivatives that inhibit toxin activity
S L Purkerson-Parker1, L A Fieber, K S Rein
1Neurotoxicology Division MD-74B, University of North Carolina Curriculum in Toxicology, United States Environmental Protection Agency, NC 27711, USA.
Chemistry & Biology
|June 30, 2000
Summary
Modified brevetoxins can act as antagonists, blocking the effects of marine neurotoxins on sodium channels. These brevetoxin derivatives retain binding ability but alter channel activity, highlighting the K-ring sidechain
Area of Science:
- Marine neurotoxicology
- Ion channel pharmacology
Background:
- Brevetoxins are marine neurotoxins that disrupt voltage-gated sodium (Na+) channel function.
- Two brevetoxin derivatives were identified with antagonist properties, differing from typical brevetoxin pharmacology.
Purpose of the Study:
- To investigate the pharmacological properties of brevetoxin derivatives.
- To determine the role of specific molecular modifications in brevetoxin activity and binding.
Main Methods:
- Electrophysiological studies on Na+ channels.
- Assessment of brevetoxin derivative binding affinity.
- Evaluation of antagonist activity on PbTx-3-exposed and unexposed Na+ channels.
Main Results:
- Brevetoxin derivatives retained receptor binding but did not elicit Na+ channel openings.
- alpha-Naphthoyl-PbTx-3 functioned as a brevetoxin antagonist without affecting unexposed Na+ channels.
- beta-Naphthoyl-PbTx-3 reduced Na+ channel openings in the absence of brevetoxin exposure.
Conclusions:
- Modifications to the brevetoxin molecule can yield antagonists with altered pharmacological profiles.
- Significant modifications to the K-ring sidechain impact pharmacological properties without affecting binding.
- The K-ring sidechain is crucial for the native pharmacological activity of brevetoxins.
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