The actions of epinephrine on muscles are not dependent on either oxidative metabolism or on the energy produced from carbohydrate through the Embden-Meyerhof glycolytic pathway.
Nonetheless, the activation of glycogenolysis may be important for the muscular effects of epinephrine.
The apparent discrepancies of the two statements relating to carbohydrate metabolism may be resolved by findings which implicate the hexosemonophosphates in the control of muscle contractility.
In their responses to epinephrine, muscles appear to fall into two groups: 1) excited smooth muscles which lose potassium, and 2) inhibited smooth muscle, skeletal muscle and cardiac muscle which retain or increase their potassium.
Changes in the ionic environment of various muscle cells modify the degree of response and, in some instances, the duration of the response to epinephrine.