The effect of pyridoxine deficiency on muscle and liver phosphorylase of two inbred strains of mice

Effect of Vitamin B6 Deficiency on Glycogen Metabolism in the Skeletal Muscle, Heart, and Liver of Rats.

“…In some previous studies on the phosphorylase activity in the muscle of pyridoxine-deficient animals, the enzyme activity was found to be reduced (11)(12)(13), whereas in others it was not decreased, even though aspartate and alanine ami notransferae activities in the muscle were decreased (14,15). In this study we observed a decrease in the amount of phosphorylase and an increase in the content of glycogen in the muscle of VB6-deficient rats.…”

“…Phosphorylases contain pyridoxal phosphate, as a cofactor, covalently bound via a Schiff base to an active site lysine (9,10). There have been several reports on the effects of vitamin B6 (VB6) deficiency on phosphorylase, but the results were not consistent; for instance, there are reports of depletion of muscle phosphorylase in VB6-deficient rats and mice (11)(12)(13) and other reports of a normal level of phos phorylase in gastrocnemius muscle in VB6-deficient rats (14,15).…”

Glycogen storage diseases in animals and their potential value as models of human disease

“…After cessation of the Acarbose treatment, the condition is slowly reversible. Enzymatic studies were not performed in the treated animals, but Acarbose is a known competitive (Schmidt et al, 1977) inhibitor of intestinal ~- Bardens, 1966Erickson et al, 1968Gluecksohn-Waelsch and Cori, 1970;Trigg and Gluecksohn-Waelsch, 1973;Thorndike et al, 1973;Gluecksohn-Waelsch et al, 1974Thaler et al, 1976;Garland et al, 1976;Gluecksohn-Waelsch, 1979Richards et al, 1977Jolly et al, 1977;Cook et al, 1978Cook et al, , 1980Edwards and Richards, 1979;Dorling et aL, t981;Howell et al, 1981O'Sullivan et al, 1981Manktelov and Harttey, 1975 Lyon and Porter, 1962, 1963Lyon et al, 1967;Hornbrook and Lyon, 1970;Gross and…”

McArdle's disease: Molecular genetics and metabolic consequences of the phenotype

“…The large size of the muscle phosphorylase vitamin B, pool means that turnover of this protein has the potential to provide vitamin B, to the body under normal dietary conditions, as proposed by Krebs and FisherI5 and supported by other experi-,,,ts. 6,7,13,16 We estimate that degradation of muscle glycogen phosphorylase could deliver about 1-2 mg (1 % of the total pool) of vitamin B, to the fast body pool every day-an amount equivalent to the daily requirement of this ~i t a r n i n .~ In the long term, this quantity must be replaced during resynthesis of phosphorylase but the phosphorylase pool could act as a short-term "buffer" although we stress that myophosphorylase is not a store of vitamin B,.…”