5-HT₄ Receptor Antagonist

GR125487 is a highly selective and potent 5-HT4 receptor (5-HT4 receptor) antagonist with a K_d value of 0.1 nM. GR125487 has an extremely low affinity for 5-HT3 receptors (K_d > 1 μM). GR125487 completely antagonizes the memory-promoting effect of BIMU1, and its administration alone has no significant effect on basic social memory. GR125487 can be used for the study of social olfactory memory.

SC-53606 is a potent and selective 5-HT₄ receptor antagonist, with a pA2 value of 8.13. SC-53606 acts as an antagonist of 5-HT₄ receptor-mediated relaxation of Carbachol (HY-B1208)-induced contractions.

SB-203186 is a highly selective 5-HT₄ receptor antagonist. SB-203186 exhibits a potent competitive antagonistic effect, with its pK_B value being 8.3 in the isolated right atrium model of piglets. SB-203186 can dose-dependently shift the 5-HT-induced tachycardia curve to the right, and does not inhibit the maximum response. SB-203186 is an efficient 5-HT₄ antagonist in pig and human atria, but has no significant inhibitory effect in rat atria. SB-203186 can be used for the study of diseases such as arrhythmias and abnormal myocardial contraction.

RS-23597 is a 5-HT4R antagonist with a K_i value of 19 nM against guinea pig 5-HT4R. RS-23597 inhibits the relaxation of the esophageal muscularis mucosae in rats. RS-23597 regulates 5-HT4R-Gs protein coupling and triggers the Gs-mediated cAMP signaling pathway. RS-23597 is applicable to the research of neurological diseases.