Papaverine decreases the efflux of42K in guinea-pig atrial heart muscle

  • Hermann Nawrath


The effects of papaverine on resting potential and efflux of42K were investigated in guinea-pig left atria. Papaverine significantly reduced the potassium efflux in beating preparations. In resting preparations, the efflux of potassium was only slightly affected. However, the resting potential was significantly reduced by papaverine by about 5 mV.

The effect of papaverine on the potassium conductance may be related to the positive inotropic effect of the drug in atrial heart muscle, since the duration of the action potential is prolonged and possibly therefore the calcium entry during excitation improved.

Key words

Papaverine Resting potential Potassium efflux Atrial heart muscle Force of contraction 


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Copyright information

© Springer-Verlag 1980

Authors and Affiliations

  • Hermann Nawrath
    • 1
  1. 1.Pharmakologisches Institut der Universität MainzMainzFederal Republic of Germany

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