Cardiac effects of ephedrine, norephedrine, mescaline, and 3,4-methylenedioxymethamphetamine (MDMA) in mouse and human atrial preparations
Naunyn-Schmiedeberg s Archives of Pharmacology November 1, 2022 Joachim Neumann, Karyna Azatsian, Christian Höhm et al. 7 citations
Ephedrine, norephedrine, and MDMA, but not mescaline, increased the force of contraction and beating rate in isolated mouse and human heart tissue preparations, starting at concentrations of 1–3 µM. These effects were less potent than those of isoprenaline and were accompanied by increased phosphorylation of troponin’s inhibitory subunit. Cocaine or propranolol greatly attenuated the effects, suggesting these drugs act indirectly by releasing noradrenaline in the human atrium. Mescaline showed no inotropic effect even with phosphodiesterase inhibitors. The findings indicate that ephedrine, norephedrine, and MDMA can be classified as indirect sympathomimetics in human atrial muscle, which may contribute to cardiac arrhythmias and fatal intoxication.