1. Autorhythmic cells and the funny current & 2. Autonomic modulation of heart rate

What creates the pacemaker potentail?

The inward Na current

Why is funny channel called that?

Because it is activated by hyper-polarization rather than depolarization

SA-node cells set the normal rhythm at about _. The AV node can produce a slower rhythm of about _, and Purkinje fibers can produce about _.

70 beats per minute, 50 beats per minute, 25 to 40 beats per minute

What is released with sympathetic stimulation and what occurs as a result?

epinephrine and norepinephrine; increased Na and Ca current, which steepens pacemaker slow and raises average membrane potential, as a result threshold is reaches sooner and HR increases

What is released with parasympathetic stimulation and what occurs as a result?

acetylcholine; increased K efflux and decreased Ca influx, which hyperpolarizes the cell and causes threshold to be reached later, lowering the HR.