Potential-dependent inhibition of cardiac Ca2+ inward currents by Ro 40-5967 and verapamil: relation to negative inotropy

Eur J Pharmacol. 1991 Apr 17;196(2):205-7. doi: 10.1016/0014-2999(91)90430-x.


Ro 40-5967 is a structurally novel Ca2+ channel blocker which binds to the [3H]desmethoxyverapamil receptor in cardiac membranes with a potency similar to that of verapamil but which has considerably fewer negative inotropic effects. In the present study, the inward Ca2+ current was measured in isolated myocytes with the whole-cell patch-clamp technique. It was found that at a physiological membrane potential (-80 mV) Ro 40-5967 was also less potent than verapamil in inhibiting this current, and that negative inotropy and Ca2+ channel blockade were correlated.

Publication types

  • Comparative Study

MeSH terms

  • Animals
  • Benzimidazoles / pharmacology*
  • Calcium Channel Blockers / pharmacology
  • Calcium Channels / drug effects*
  • Depression, Chemical
  • Guinea Pigs
  • In Vitro Techniques
  • Membrane Potentials
  • Mibefradil
  • Myocardial Contraction / drug effects*
  • Tetrahydronaphthalenes / pharmacology*
  • Verapamil / pharmacology*


  • Benzimidazoles
  • Calcium Channel Blockers
  • Calcium Channels
  • Tetrahydronaphthalenes
  • Mibefradil
  • Verapamil