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Updated: Jun 26, 2026
07:42
Nerve Excitability Assessment in Chemotherapy-induced Neurotoxicity
Published on: April 26, 2012
Oxaliplatin neurotoxicity--no general ion channel surface-charge effect
Amir Broomand1, Elin Jerremalm, Jeffrey Yachnin
1Department of Oncology-Pathology, Karolinska Institutet and Karolinska Pharmacy, Karolinska University Hospital, Solna, Stockholm, Sweden. amibr@ibk.liu.se
Journal of Negative Results in Biomedicine
|January 14, 2009
Summary
Oxaliplatin, a chemotherapy drug, did not affect Shaker K+ channels, suggesting its neurotoxicity mechanism is not a general surface charge alteration. Specific effects on mutated channels were also not observed.
Area of Science:
- Neuroscience
- Pharmacology
- Molecular Biology
Background:
- Oxaliplatin is a platinum-based chemotherapy agent.
- Neurotoxicity is a primary dose-limiting side effect of oxaliplatin.
- Voltage-gated ion channels are implicated in oxaliplatin-induced neurotoxicity.
Purpose of the Study:
- To investigate the molecular mechanisms underlying oxaliplatin-induced neurotoxicity.
- To determine the effects of oxaliplatin and its chloride complex on the voltage-gated Shaker K+ channel.
- To explore potential surface charge modifications or direct binding interactions.
Main Methods:
- Utilized Xenopus oocytes expressing the Shaker K+ channel.
- Employed two-electrode and cut-open oocyte voltage clamp techniques.
- Examined effects on wild-type and cysteine-mutated Shaker channels (E418C, R362C/F416C).
Main Results:
- Oxaliplatin and its monochloro complex showed no effect on Shaker wild-type channel current amplitude, time course, or voltage dependence.
- No effects were observed on Shaker channels with single (E418C) or double (R362C/F416C) cysteine mutations.
- These findings indicate a lack of general surface-charge effect on the Shaker K+ channel.
Conclusions:
- Oxaliplatin does not appear to exert its effects through a general surface-charge mechanism on the Shaker K+ channel.
- The drug did not directly interact with the specific cysteine residues tested in mutated Shaker channels.
- The study suggests oxaliplatin's neurotoxic effects may involve more specific molecular targets than previously hypothesized for ion channels.
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