Ion channel ligands

A number of agonists can act through several receptor classes, e.g., ion channels and G-protein-coupled receptors. To set receptor subtypes permanently linked to ion channels ( ligand-gated ion channels) apart... 

For differentiation of G-protein-coupled receptor sub-types from subtypes permanently linked to ion channels (ligand-gated ion channels) the terms metabotropic versus ionotropic receptors, respectively, are used. Prime examples of metabotropic receptors are given by the lnGlu receptor family of G-protein-coupled glutamate receptors. 

Opening membrane ion channels. These are the ion-channel ligands, which bind to and selectively open ion channels of nematode muscle. Three types of ion channel are the sites of action of this group of anthelmintics ... 

Figure 4.14 Gated ion channel (ligand activated, acetylcholine) at neuromuscular junction, (a) receptor sites unoccupied and gate closed (b) acetylcholine receptor sites occupied and gate is open allowing influx of ion...

Voltage-gated ion channels Ligand-gated ion channels G-proteins... 

Which of the following is/are classified as ligand-gated ion channel ligands a cyclic-AMP... 

Thus, this recent example nicely demonstrates that ion channel ligands can be valuable starting points for the identification of drugs acting against other members of the ion channel protein family. 

Receptors of mediators inclnding an intrinsic ion channels (ligand-gated ion channels snch as nicotinic receptors), or an enzyme activity (i.e. a tyrosine kinase activity such as insnlin receptors, or ganylyl cyclase activity such as ANF receptors) have ligands for their receptor part (agonists and antagonists) as well as for their ion channel (openers and inhibitors or blockers) or enzyme part (inhibitors). 

CapeDi, A.M., Feriani, A., Tedesco, G. and Pozzan, A. (2006) Generation of a focused set of GSK compounds biased toward ligand-gated ion-channel ligands./. Chem. Inf. Model, 46, 659-664. 

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