Neural and humoral induction of hepatic glycogenolysis occurs via different pathways.
Sympathetic nerve stimulation activates alpha adrenergic receptors to produce what is
probably a cyclic AMP independent, Ca++ dependent activation of glycogen phosphorylase.
Evidence suggests that phosphorylase 'a'is activated by inhibition of phosphorylase
phosphatase and perhaps by activation of phosphorylase kinase. Blood borne
catecholamines act via beta adrenergic receptors to produce a cyclic AMP dependent …