Studies on glycogen synthesis in pigeon liver homogenates. Glycogen synthesis from glucose monophosphates and uridine diphosphate glucose

• Published in: Biochemical journal 1967-11, Vol.105 (2), p.515-519
• Main Author: Nigam, V N
• Format: Article
• Language: English
• Subjects: Animals; Arsenicals - pharmacology; Carbon Isotopes; Columbidae; Cytoplasm - metabolism; Depression, Chemical; Dinitrophenols - pharmacology; Edetic Acid - pharmacology; Glucose - metabolism; Glucose-6-Phosphatase - metabolism; Kinetics; Liver Glycogen - biosynthesis; Mitochondria, Liver - metabolism; Rats; Stimulation, Chemical; Uracil Nucleotides - metabolism
• ISSN: 0264-6021; 0306-3283; 1470-8728
• DOI: 10.1042/bj1050515

Comparative time-course studies of glycogen synthesis from glucose 6-phosphate, glucose 1-phosphate and UDP-glucose show that glucose 1-phosphate forms glycogen at an initial rate faster than that obtained with glucose 6-phosphate and UDP-glucose. After 5min. the rates from glucose monophosphates are considerably slower. 2,4-Dinitrophenol decreases glycogen synthesis from both glucose monophosphates, whereas arsenate and EDTA increase glycogen synthesis from glucose 1-phosphate and inhibit the reaction from glucose 6-phosphate, galactose and galactose 1-phosphate. Mitochondria-free pigeon liver cytoplasmic fraction forms less glycogen from glucose monophosphates than does the whole homogenate. 2-Deoxyglucose 6-phosphate inhibits glycogen synthesis from glucose monophosphates. Glycogen formation from UDP-glucose is relatively unaffected by dinitrophenol, by arsenate, by EDTA, by 2-deoxyglucose 6-phosphate and by the removal of mitochondria from the whole homogenate.