The epinephrine signaling pathway plays a role in regulating glucose homeostasis in muscle cells. The signaling pathway is activ
ated by the binding of epinephrine to the beta-2 adrenergic receptor. A simplified model of the epinephrine signaling pathway is represented in Figure 1. Cyclic AMP phosphodiesterase is an enzyme that catalyzes the conversion of cyclic AMP to a different molecule. Which of the following best predicts the effect of inhibiting cyclic AMP phosphodiesterase in a muscle cell stimulated by epinephrine?
When cyclic AMP phosphodiesterase is inhibited in a muscle that is stimulated by epinephrine,there will be a crucial effect of making the phosphorylase kinase to remain active,this active state of the phosphorylase kinase is because the associated protein kinase A will not be deactivated any longer.
Epinephrine signaling pathway has varying steps,but the preceding step occurs when the associating hormone binds to the receptor of the epinephrine in the cell surface,the receptor then changes shape when the hormone triggers it,this makes the receptor to move to it's active form. GDP( guanosine diphosphate) is released after the G protein ( guanine nucleotide-binding proteins) binds to the receptor that is activated,the G protein then takes up a molecule of GTP (guanosine triphosphate) .
