How Adrenaline and Acetylcholine Affect Heart Rate

In this episode, Leslie Samuel discusses how adrenaline and acetylcholine affect heart rate. Adrenaline, released from the adrenal gland, increases heart rate by enhancing sodium and calcium conductance, leading to faster action potentials. Conversely, acetylcholine increases potassium conductance, causing hyperpolarization and slower depolarization, which decreases heart rate. The episode also recaps the pacemaker potential and spontaneous signals in the heart, and concludes with a mention of additional resources available on the Interactive Biology website.

What happens to the conductance of potassium when acetylcholine is released?

Explain the difference in depolarization speed between adrenaline and acetylcholine.