TY - JOUR
T1 - Effects of bepridil on force development and transmembrane electrical activity of adult canine purkinje strands
T2 - Comparison with nisoldipine and lidocaine
AU - Lathrop, David A.
AU - Murphy, Anne M.
AU - Humphreys, Teresa
AU - Schwartz, Arnold
PY - 1985/12/3
Y1 - 1985/12/3
N2 - Superfusion of a bepridil containing normal Tyrode solution produced a concentration-dependent decrease in force development and shortening of action potential duration in isolated Purkinje strands. At a concentration close to the 50% inhibitory concentration for effects on force development and action potential duration, bepridil blocked 'slow' action potentials in potassium depolarized, isoproterenol-restored Purkinje strands. When the concentration-response relations for decreasing force development and shortening action potential duration were compared to those of nisoldipine and other calcium entry inhibitors, bepridil was the least potent. Bepridil also showed a concentration-dependent effect on the maximum rate of rise of the Purkinje fiber action potential upstroke similar to, though less potent than that of lidocaine. In addition, like lidocaine, bepridil shifted the membrane responsiveness curve of the Purkinje strands to the left. These findings indicate that bepridil produced effects that are consistent with its classification as a calcium entry inhibitor (class IV antiarrhythmic), as well as effects that are 'lidocaine-like' (class I antiarrhythmic).
AB - Superfusion of a bepridil containing normal Tyrode solution produced a concentration-dependent decrease in force development and shortening of action potential duration in isolated Purkinje strands. At a concentration close to the 50% inhibitory concentration for effects on force development and action potential duration, bepridil blocked 'slow' action potentials in potassium depolarized, isoproterenol-restored Purkinje strands. When the concentration-response relations for decreasing force development and shortening action potential duration were compared to those of nisoldipine and other calcium entry inhibitors, bepridil was the least potent. Bepridil also showed a concentration-dependent effect on the maximum rate of rise of the Purkinje fiber action potential upstroke similar to, though less potent than that of lidocaine. In addition, like lidocaine, bepridil shifted the membrane responsiveness curve of the Purkinje strands to the left. These findings indicate that bepridil produced effects that are consistent with its classification as a calcium entry inhibitor (class IV antiarrhythmic), as well as effects that are 'lidocaine-like' (class I antiarrhythmic).
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U2 - 10.1016/0014-2999(85)90139-6
DO - 10.1016/0014-2999(85)90139-6
M3 - Article
C2 - 3878795
AN - SCOPUS:0022344817
VL - 118
SP - 283
EP - 292
JO - European Journal of Pharmacology
JF - European Journal of Pharmacology
SN - 0014-2999
IS - 3
ER -