Glycogen is a high molecular polysaccharide composed of glucose units. It is one of the main storage
forms of sugar. It is mainly stored in the liver and muscle as backup energy, and is called liver glycogen
and muscle glycogen, respectively. Glycogen can regulate blood glucose concentration. Glycogen can be
synthesized in the liver when blood glucose rises. When blood sugar decreases, liver glycogen is broken
down into glucose to supplement blood sugar. Therefore, liver glycogen is important to maintain the
relative balance of blood sugar. Muscle glycogen is a form of glycogen storage in muscles. When lots of
blood sugar is consumed during strenuous exercise, muscle glycogen cannot be broken down directly into
blood sugar. It must first be broken down to produce lactic acid, which is circulated to the liver with the
blood, and transformed into liver glycogen through glycogen glucose.
Determination principle: anthrone method. Glycogen is extracted with strong alkaline extract, and the
glycogen content is measured using an anthrone method under strongly acidic conditions.
Reagents and Equipment Required but Not Provided.
Spectrophotometer, desk centrifuge, transferpettor, 1mL glass cuvette, mortar, concentrated sulfuric acid
(H2SO4) and distilled water.
