Epinephrine also actually plays an important role, but a smaller role in liver cells. Epinephrine binds to beta adrenergic receptors as well as alpha adrenergic receptors. When it binds to the beta adrenergic receptor it basically follows a similar pathway to the pathway outlined here. But when epinephrine, which is, by the way, a tyrosine based hormone, when epinephrine actually binds onto the alpha adrenergic receptor, what it does is initiates the phosphonosatide cascade. And what that cascade actually does is it basically stimulates the release of calcium ions that are stored inside the lumen of the endoplasm reticulum of these liver cells. And so we have the influx of these calcium ions into the cytoplasm of the liver cell.