Microenvironmental Properties and Conformational Changes in Glycogen Phosphorylase
Glycogen is a major source of energy for muscle contraction. Its breakdown and synthesis are regulated by the contractile state of the tissue as well as by the neural and hormonal control of the muscle, through changes in the phosphorylation state of glycogen phosphorylase and glycogen synthase. When muscle is stimulated electrically, calcium ions released from sarcoplasmic reticulum not only initiate muscle contraction but also activate phosphorylase kinase. As a result, the phosphorylation state of glycogen phosphorylase is increased and glycogenolysis is accelerated to provide the ATP required to sustain muscle contraction.
KeywordsGlycogen Phosphorylase Sodium Cholate Rabbit Skeletal Muscle Difference Absorption Spectrum Fluorescein Derivative
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