Allosteric modulators of ligand-gated receptor channels induce conformational changes of the entire protein that alter potencies and efficacies for orthosteric ligands, expressed as the half maximal effective concentration and maximum current amplitude, respectively. The influence of allostery on channel pore size, an issue not previously addressed, was studied.
Zemkova H, Khadra A, Rokic MB, Tvrdonova V, Sherman A, Stojilkovic SS: Allosteric regulation of the P2X4 receptor channel pore dilation.
http://link.springer.com/article/10.1007%2Fs00424-014-1546-7