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Method for Identifying Small Molecule Inhibitors of the Protein-protein Interaction Between HCN1 and TRIP8b
Published on: November 11, 2016
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HCN channels and absence seizures
Vincenzo Crunelli1, Francois David2, Tatiana P Morais3
1Neuroscience Division, School of Bioscience, Cardiff University, Cardiff, UK.
Neurobiology of Disease
|March 31, 2023
Summary
Hyperpolarization-activated cyclic nucleotide-gated (HCN) channels are linked to absence seizures (ASs). While some HCN channel gene variants cause ASs, blocking all HCN channels can abolish them, suggesting complex roles in epilepsy.
Area of Science:
- Neuroscience
- Epileptology
- Channelopathies
Background:
- Absence seizures (ASs) are linked to abnormal currents (Ih) generated by hyperpolarization-activated cyclic nucleotide-gated (HCN) channels in neurons.
- Genetic studies in Childhood Absence Epilepsy identified limited HCN1 variants, including a loss-of-function mutation, complicating the understanding of HCN channel roles in ASs.
Purpose of the Study:
- To systematically analyze the role of different HCN channel isoforms (HCN1, HCN2, HCN4) in the generation and maintenance of absence seizures.
- To reconcile seemingly contradictory findings regarding HCN channel function in AS models.
Main Methods:
- Critical analysis of evidence from established AS models and normal animals.
- Examination of studies involving area- and time-selective ablation of HCN1, HCN2, and HCN4 channels.
- Review of pharmacological studies blocking HCN channel isoforms.
Main Results:
- Knockout of HCN1 in rats and HCN2 in mice induced ASs.
- Pharmacological blockade of all HCN channel isoforms abolished genetically determined ASs.
- Contradictory results are reconciled by considering the opposing effects of Ih on cellular excitability and network function.
Conclusions:
- Pan-HCN blockers show potential for treating human ASs based on current evidence.
- Developing HCN isoform-selective drugs is crucial for understanding AS mechanisms and exploring new clinical applications.
Keywords:
CortexDendritic summationHCN1–4I(h)Network resonanceSpike-and-wave dischargesThalamic reticular nucleusThalamusMore Related Videos
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