Download MendeleyA Novel Mu-Conopeptide, Cniiic, Exerts Potent and Preferential Inhibition of Na(V) 1.2/1.4 Channels and Blocks Neuronal Nicotinic Acetylcholine Receptors.
Favreau, P., Benoit, E., Hocking, H.G., Carlier, L., D'Hoedt, D., Leipold, E., Markgraf, R., Schlumberger, S., Cordova, M.A., Gaertner, H., Paolini-Bertrand, M., Hartley, O., Tytgat, J., Heinemann, S.H., Bertrand, D., Boelens, R., Stocklin, R., Molgo, J.(2012) Br J Pharmacol 166: 1654
- PubMed: 22229737
- DOI: https://doi.org/10.1111/j.1476-5381.2012.01837.x
- Primary Citation of Related Structures:
2YEN - PubMed Abstract:
The µ-conopeptide family is defined by its ability to block voltage-gated sodium channels (VGSCs), a property that can be used for the development of myorelaxants and analgesics. We characterized the pharmacology of a new µ-conopeptide (µ-CnIIIC) on a range of preparations and molecular targets to assess its potential as a myorelaxant. µ-CnIIIC was sequenced, synthesized and characterized by its direct block of elicited twitch tension in mouse skeletal muscle and action potentials in mouse sciatic and pike olfactory nerves. µ-CnIIIC was also studied on HEK-293 cells expressing various rodent VGSCs and also on voltage-gated potassium channels and nicotinic acetylcholine receptors (nAChRs) to assess cross-interactions. Nuclear magnetic resonance (NMR) experiments were carried out for structural data. Synthetic µ-CnIIIC decreased twitch tension in mouse hemidiaphragms (IC(50) = 150 nM), and displayed a higher blocking effect in mouse extensor digitorum longus muscles (IC = 46 nM), compared with µ-SIIIA, µ-SmIIIA and µ-PIIIA. µ-CnIIIC blocked Na(V)1.4 (IC(50) = 1.3 nM) and Na(V)1.2 channels in a long-lasting manner. Cardiac Na(V)1.5 and DRG-specific Na(V)1.8 channels were not blocked at 1 µM. µ-CnIIIC also blocked the α3β2 nAChR subtype (IC(50) = 450 nM) and, to a lesser extent, on the α7 and α4β2 subtypes. Structure determination of µ-CnIIIC revealed some similarities to α-conotoxins acting on nAChRs. µ-CnIIIC potently blocked VGSCs in skeletal muscle and nerve, and hence is applicable to myorelaxation. Its atypical pharmacological profile suggests some common structural features between VGSCs and nAChR channels.
- Atheris Laboratories, Bernex-Geneva, Switzerland.
Organizational Affiliation:
