How does adrenaline accelerate the heart?

  title={How does adrenaline accelerate the heart?},
  author={Hilary F. Brown and Dario DiFrancesco and S. J. Noble},
THE way in which adrenaline acts on the sinoatrial (SA) node to accelerate the heart rate has hitherto been obscure. However, in various other parts of the heart adrenaline increases the slow inward (Ca2+/Na+) current1–4, and voltage-recording experiments have indicated that adrenaline also has this action in the sinus region5–7. In the voltage-clamp experiments reported here, we find that adrenaline does indeed increase the slow inward current in the SA node of the rabbit, but that it also… Expand

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