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Published on: March 11, 2021
Structure-activity relationship studies of spinorphin as a potent and selective human P2X(3) receptor antagonist
Kwan-Young Jung1, Hyoun Duk Moon, Ga Eun Lee
1Department of Life Science, Gwangju Institute of Science and Technology, Gwangju 500-712, Republic of Korea.
Abstract:
Spinorphin, an endogenous antinociceptive peptide (LVVYPWT), showed potent and non-competitive antagonism at the ATP-activated human P2X3 receptor (IC50 = 8.3 pM) in a two-electrode voltage clamp assay with recombinant human P2X3 receptors expressed in Xenopus oocytes. Single alanine substitutions from 1st to 4th amino acids and the cyclic form of LVVYPWT sustained antagonistic properties at the human P2X3 receptors, whereas the threonine to alanine substitution resulted in an enhancing effect of the agonistic activity.
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