biostudies-literatureHesse CDeutsche Forschungsgemeinschaft11133https://www.ebi.ac.uk/biostudies/studies/S-EPMC11508481biostudies-literatureUnknown25(20)Tegaserod (1-{[(5-methoxy-1H-indol-3-yl)methyliden]amino}-3-pentylguanidine) is a potent agonist at human recombinant 5-HT₄ serotonin receptors. Consequently, tegaserod is utilized in the treatment of bowel diseases. The objective of this study was to test the hypothesis that tegaserod stimulates human cardiac atrial 5-HT₄-receptors via cyclic adenosine monophosphate (cAMP)-dependent pathways. Tegaserod exerted positive inotropic effects (PIEs) and positive chronotropic effects (PCEs) in isolated left and right atrial preparations, respectively, from mice with cardiac-specific overexpression of the human 5-HT₄ serotonin receptor (5-HT₄-TG) in a concentration- and time-dependent manner. However, no effect was observed in the hearts of littermates International journal of molecular sciencesTegaserod Stimulates 5-HT<sub>4</sub> Serotonin Receptors in the Isolated Human Atrium.PMC11508481PO732Muller FENeumann JCompan VPonimaskin EHofmann BHesse CGergs UfalseTegaserod Stimulates 5-HT<sub>4</sub> Serotonin Receptors in the Isolated Human Atrium.Tegaserod (1-{[(5-methoxy-1H-indol-3-yl)methyliden]amino}-3-pentylguanidine) is a potent agonist at human recombinant 5-HT₄ serotonin receptors. Consequently, tegaserod is utilized in the treatment of bowel diseases. The objective of this study was to test the hypothesis that tegaserod stimulates human cardiac atrial 5-HT₄-receptors via cyclic adenosine monophosphate (cAMP)-dependent pathways. Tegaserod exerted positive inotropic effects (PIEs) and positive chronotropic effects (PCEs) in isolated left and right atrial preparations, respectively, from mice with cardiac-specific overexpression of the human 5-HT₄ serotonin receptor (5-HT₄-TG) in a concentration- and time-dependent manner. However, no effect was observed in the hearts of littermates 2024-01-01T00:00:00Z2024 Oct2025-04-26T00:12:55.475Z2025-04-06T09:42:29.914ZS-EPMC115084813945691510.3390/ijms252011133