- What is the difference between a hormone and a neurotransmitter?
- Epinephrine (a.k.a. adrenaline) can act as both a hormone and a neurotransmitter, and its actions vary by tissue type.
a. How does epinephrine affect heart muscle tissue, and how does this in turn affect pulse rate?
b. Given that caffeine triggers the release of epinephrine, how is caffeine expected to affect pulse rate?