caa a22 4500 46907986X CHVBK 20180323132947.0 cr unu---uuuuu 170328e19920201xx s 000 0 eng 10.1007/BF00165743 doi (NATIONALLICENCE)springer-10.1007/BF00165743 Effects of the K+ channel blocker tedisamil on 86Rb efflux induced by cromakalim, high potassium and noradrenaline, and on mechanical tension in rabbit isolated vascular smooth muscle [Elektronische Daten] [Volker Kreye, Dietmar Pfründer, Ursula Theiss] Summary: Tedisamil, a new bradycardic agent with an inhibitory action on K+ channels in cardiac muscle, was found to inhibit in a non-competitive manner the relaxation induced by the K+ channel opener cromakalim in noradrenaline-stimulated helical strips from rabbit aortae. Tedisamil tended to be more potent in this respect than glibenclamide; the latter however competitively antagonized the cromakalim-induced relaxation. In rabbit aorta preloaded with 86Rb as a marker of K+, 10 μmol/l tedisamil inhibited the 86Rb efflux induced by 10 μmol/l cromakalim. — While the 86Rb efflux evoked by depolarization with 100 mmol/l K+ aspartate was inhibited by tedisamil, too, the rise of 86Rb efflux induced by noradrenaline was unaffected by the drug. In non-stimulated rabbit aorta, tedisamil increased mechanical tension in a concentration-dependent manner (EC50 for peak contractions: 32 μmol/l; for maintained tension: 24 μmol/l), and enhanced 86Rb efflux. Both stimulant actions were antagonized by the calcium antagonist diltiazem. In conclusion, tedisamil affects different K+ channels in vascular smooth muscle. Its stimulant effects are assumed to be secondary to membrane depolarization and subsequent activation of voltage-dependent Ca2+ channels. Springer-Verlag, 1992 Cardiovascular agents nationallicence Diltiazem nationallicence Glibenclamide nationallicence K+ channel openers nationallicence Rabbit aorta nationallicence Kreye Volker II. Physiologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 326, W-6900, Heidelberg, Federal Republic of Germany aut Pfründer Dietmar II. Physiologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 326, W-6900, Heidelberg, Federal Republic of Germany aut Theiss Ursula II. Physiologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 326, W-6900, Heidelberg, Federal Republic of Germany aut Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 345/2(1992-02-01), 238-243 0028-1298 345:2<238 1992 345 210 https://doi.org/10.1007/BF00165743 text/html Onlinezugriff via DOI 1 research-article jats NATIONALLICENCE 856 40 https://doi.org/10.1007/BF00165743 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Kreye Volker II. Physiologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 326, W-6900, Heidelberg, Federal Republic of Germany aut NATIONALLICENCE 700 1- Pfründer Dietmar II. Physiologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 326, W-6900, Heidelberg, Federal Republic of Germany aut NATIONALLICENCE 700 1- Theiss Ursula II. Physiologisches Institut der Universität Heidelberg, Im Neuenheimer Feld 326, W-6900, Heidelberg, Federal Republic of Germany aut NATIONALLICENCE 773 0- Naunyn-Schmiedeberg's Archives of Pharmacology Springer-Verlag 345/2(1992-02-01), 238-243 0028-1298 345:2<238 1992 345 210 Metadata rights reserved Springer special CC-BY-NC licence nationallicence BK010053 XK010053 XK010000 NATIONALLICENCE NATIONALLICENCE NL-springer