caa a22 4500 475775155 CHVBK 20180406123629.0 cr unu---uuuuu 170329e20000801xx s 000 0 eng 10.1023/A:1007293812007 doi (NATIONALLICENCE)springer-10.1023/A:1007293812007 The effect of the Fusarium metabolite beauvericin on electromechanical and -physiological properties in isolated smooth and heart muscle preparations of guinea pigs [Elektronische Daten] [R. Lemmens-Gruber, B. Rachoy, E. Steininger, K. Kouri, P. Saleh, R. Krska, R. Josephs, M. Lemmens] The electromechanical and -physiological effects of beauvericin were studied in isolated smooth and heart muscle preparations of the guinea pig. Beauvericin concentration-dependently decreased the force of contraction in precontracted (60 mM KCl) terminal ilea with an IC50 of 0.86 μM, and in electrically stimulated (1 Hz) papillary muscles with an IC50 of 18 μM. This negative inotropic effect in papillary muscles was antagonised in a non-competitive way by increased extracellular calcium concentrations. Spontaneous activity in right atria was affected at concentrations >10 μM beauvericin. The negative chronotropic effect was less pronounced than the negative inotropic effect. In action potentials of electrically driven (1 Hz) papillary muscles, 10 μM beauvericin significantly decreased membrane resting potential until unexcitability of the preparation occurred. Despite depolarisation of the membrane the maximum rate of rise of the action potential was not changed. The action potential duration was shortened, but the decrease was only significant at times to 20% and 50% repolarisation. These data, derived from the electrophysiological experiments, not only imply an effect on the calcium current as suggested by the effects on contractility, but also an interaction with the sodium inward and potassium outward currents. Kluwer Academic Publishers, 2000 action potential nationallicence beauvericin nationallicence force of contraction nationallicence fusarium metabolite nationallicence smooth muscle nationallicence heart muscle nationallicence Lemmens-Gruber R. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut Rachoy B. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut Steininger E. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut Kouri K. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut Saleh P. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut Krska R. Center for Analytical Chemistry, Institute for Agrobiotechnology (IFA-Tulln), Konrad Lorenz Str. 20, A-3430, Tulln, Austria aut Josephs R. Center for Analytical Chemistry, Institute for Agrobiotechnology (IFA-Tulln), Konrad Lorenz Str. 20, A-3430, Tulln, Austria aut Lemmens M. Department of Plant Production Biotechnology, Konrad Lorenz Str. 20, A-3430, Tulln, Austria aut Mycopathologia Kluwer Academic Publishers 149/1(2000-08-01), 5-12 0301-486X 149:1<5 2000 149 11046 https://doi.org/10.1023/A:1007293812007 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1023/A:1007293812007 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Lemmens-Gruber R. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut NATIONALLICENCE 700 1- Rachoy B. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut NATIONALLICENCE 700 1- Steininger E. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut NATIONALLICENCE 700 1- Kouri K. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut NATIONALLICENCE 700 1- Saleh P. Institute of Pharmacology and Toxicology, University of Vienna, Althansstr. 14, A-1090, Vienna, Austria aut NATIONALLICENCE 700 1- Krska R. Center for Analytical Chemistry, Institute for Agrobiotechnology (IFA-Tulln), Konrad Lorenz Str. 20, A-3430, Tulln, Austria aut NATIONALLICENCE 700 1- Josephs R. Center for Analytical Chemistry, Institute for Agrobiotechnology (IFA-Tulln), Konrad Lorenz Str. 20, A-3430, Tulln, Austria aut NATIONALLICENCE 700 1- Lemmens M. Department of Plant Production Biotechnology, Konrad Lorenz Str. 20, A-3430, Tulln, Austria aut NATIONALLICENCE 773 0- Mycopathologia Kluwer Academic Publishers 149/1(2000-08-01), 5-12 0301-486X 149:1<5 2000 149 11046 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer