Search results for "Glycogen phosphorylase"
showing 4 items of 14 documents
Control of glycolysis in vertebrate skeletal muscle during exercise
1996
The gastrocnemius muscle of the frog (Rana temporaria) has a high capacity for anaerobic glycolysis from glycogen. Glycolytic metabolites and effectors of phosphofructokinase, particularly the hexose bisphosphates, were followed in muscle during exercise (swimming between 5 s and 5 min), recovery (rest for up to 2 h after 5 min of swimming), and repeated exercise (swimming for up to 60 s after 2 h of recovery). Glycogen phosphorylase and phosphofructokinase were swiftly activated with exercise. The hexose bisphosphates followed markedly different time courses. Fructose 1,6-bisphosphate was transiently increased in both exercise and repeated exercise. This appears to be an effect rather tha…
Effects of Acute Handling Stress on Whitefish Coregonus lavaretus After Prolonged Exposure to Biologically Treated and Untreated Bleached Kraft Mill …
2000
Exposure of fish to water of impaired quality has been shown to disrupt the function of the hypothalamo-pituitary-interrenal (HPI) axis and alter the interpretation of data from field studies due to the varying effects of handling and delayed sampling on exposed and reference animals. In the present study, juvenile whitefish, Coregonus lavaretus, were exposed for 6 weeks to diluted (4-8%) untreated and biologically treated bleached kraft mill effluent (BKME) and their response to acute handling was investigated. Liver microsomal EROD activity and glycogen phosphorylase (GPase) activity, in addition to gill Na+-K+-ATPase activity, and blood hemoglobin and hematocrit levels were increased in …
Regulatory features of glycogen phosphorylase from frog brain (Rana temporaria)
1985
1. Glycogen content and the activity of glycogen phosphorylase (GPase) are much higher in brain tissue of the Common frog (Rana temporaria) than in brain tissue of mammals and birds (Table 1). 2. In phosphate buffer GPase is extracted from frog orain in a form completely active without addition of AMP and has therefore to be regarded as phosphorylase a. Several procedures to extract the b-form of the enzyme from the tissue have been unsuccessful. In resting skeletal muscle predominantly the AMP dependent b-form is present (Table 1). 3. In vitro, however, the existence of the complete interconverting system can be demonstrated. If NaF (a phosphatase inhibitor) was omitted from the homogeniza…
Metabolic enzymes in coelomic cells (eleocytes) of the polychaete Nereis virens: sex specific changes during sexual maturation
1993
The activities of some enzymes of the intermediary metabolism and the content of soluble protein and carbohydrate (glycogen plus free glucose) were measured in one type of coelomic cells (eleocytes) of the polychaete Nereis virens. Specimens used in this study were collected between 1989 and 1991 in Oosterscheldt Bay, The Netherlands, and divided into six different stages of sexual maturation as determined by the mean oocyte volume. In both sexes, the soluble protein content in eleocytes of immature individuals (11 mg ml−1 cell vol) increased three-fold. In prespawning N. virens the soluble protein content decreased to less than 2 mg protein ml−1 cell vol in females but not in males. In bot…