The enzyme in muscle which is most directly stimulated by epinephrine is
A) glycogen synthase.
B) phosphofructokinase.
C) isocitrate dehydrogenase.
D) glucose-6-phosphatase.
E) adenylate cyclase.

Question

Quizplus · Accepted Answer

Epinephrine stimulates adenylate cyclase, which leads to the formation of cyclic AMP (cAMP). cAMP then activates protein kinase A (PKA), which in turn activates enzymes involved in glycogen breakdown and glucose production (such as glycogen phosphorylase and phosphorylase kinase) while inhibiting enzymes involved in glycogen synthesis (such as glycogen synthase). This results in an increase in the availability of glucose for energy production in muscle.

The Enzyme in Muscle Which Is Most Directly Stimulated by Epinephrine