• Journal of the Korean Society of Food Science and Nutrition
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• v.28 no.6
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• pp.1226-1229
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• 1999

In order to investigate the harvest time for the production of high value added ark shell(Scapharca subcrenata) cultured at the south coast of Korea, the seasonal variations of proximate composition(mois ture, protein, fat, ash and glycogen) in the edible portions of ark shell were measured from December 1994 to December 1995. Moisture contents were the lowest in spring, but the highest in summer season being the spawning season of the S. subcrenata. The other hand, protein contents were a maximum in spring and minimum in summer. In June, just before the spawning season, fat and glycogen content was the highest, and ash content was little changed through a year. After spawning season, glycogen contents, showed decrement. In evaluating the seasonal variation of protein, moisture, and glycogen content in ark shell, the relationships of moisture protein content, moisture glycogen content and glycogen protein content show to be reverse.

• The Korean Journal of Zoology
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• v.19 no.1
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• pp.1-6
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• 1976

The glycogen content of the oocytes at the various stages of meiotic division induced during culture was determined by a microspectrophotometer. The PAS intensity decreased gradually as the meiotic resumption progressed. The amount of glycongen was also decreased in the degenerated ova. Is is concluded that the glycogen consumption in necessary for the meiotic resumption and that the glycogen loss while the germinal vesicle is intact seems to lead degeneration. These results suggest that the endogenous glycogen is important to support meiosis.

• The Korean Journal of Pharmacology
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• v.3 no.1
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• pp.27-29
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• 1967

Many investigators reported the mineral corticoid hormon-like action of Glycyrrhizin. The other investigators suggested concerning the glucocorticoid hormon-like action. Authors had been observed the glycogen content of the liver to make sure the relationship between glucocorticoid like action of Glycyrrhizin and glucose metabolism in the liver. There was significant increase in the liver glycogen content in rat fed Glycyrrhizin for two weeks, however it was confirmed that Glucuronic acid combined with Glucuronic was unable to make any influence to glycogen content. The relation concerning the effect of Glycyrrhizin on liver glycogen and its mechanism of action might be needed followup study.

• BMB Reports
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• v.35 no.3
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• pp.283-290
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• 2002

The glycogen-associated protein phosphatase (PP1G/$R_{GL}$) may play a central role in the hormonal control of glycogen metabolism in the skeletal muscle. Here, we investigated the in vivo epinephrine effect of glycogen metabolism in the skeletal muscle of the wild-type and $R_{GL}$ knockout mice. The administration of epinephrine increased blood glucose levels from 200±20 to 325±20 mg/dl in both wild-type and knockout mice. Epinephrine decreased the glycogen synthase -/+ G6P ratio from 0.24±0.04 to 0.10±0.02 in the wild-type, and from 0.17±0.02 to 0.06±0.01 in the knockout mice. Conversely, the glycogen phosphorylase activity ratio increased from 0.21±0.04 to 0.65±0.07 and from 0.30±0.04 to 0.81±0.06 in the epinephrine trated wild-type and knockout mice respectively. The glycogen content of the knockout mice was substantially lower (27%) than that of both wild-type mice; and epinephrine decreased glycogen content in the wild-type and knockout mice. Also, in Western blot analysis there was no compensation of the other glycogen targeting components PTG/R5 and R6 in the knockout mice compared with the wild-type. Therefore, $R_{GL}$ is not required for the epinephrine stimulation of glycogen metabolism, and rather another phosphatase and/or regulatory subunit appears to be involved.

• Korean Journal of Exercise Nutrition
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• v.25 no.2
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• pp.15-19
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• 2021

[Purpose] Skeletal muscle glycogen is a determinant of endurance capacity for some athletes. Ginger is well known to possess nutritional effects, such as anti-diabetic effects. We hypothesized that ginger extract (GE) ingestion increases skeletal muscle glycogen by enhancing fat oxidation. Thus, we investigated the effect of GE ingestion on exercise capacity, skeletal muscle glycogen, and certain blood metabolites in exercised rats. [Methods] First, we evaluated the influence of GE ingestion on body weight and elevation of exercise performance in rats fed with different volumes of GE. Next, we measured the skeletal muscle glycogen content and free fatty acid (FFA) levels in GE-fed rats. Finally, we demonstrated that GE ingestion contributes to endurance capacity during intermittent exercise to exhaustion. [Results] We confirmed that GE ingestion increased exercise performance (p<0.05) and elevated the skeletal muscle glycogen content compared to the nonGE-fed (CE, control exercise) group before exercise (Soleus: p<0.01, Plantaris: p<0.01, Gastrocnemius: p<0.05). Blood FFA levels in the GE group were significantly higher than those in the CE group after exercise (p<0.05). Moreover, we demonstrated that exercise capacity was maintained in the CE group during intermittent exercise (p<0.05). [Conclusion] These findings indicate that GE ingestion increases skeletal muscle glycogen content and exercise performance through the upregulation of fat oxidation.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.6
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• pp.862-869
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• 2015

The current study was designed to estimate the pork quality traits using metabolites from exsanguination blood and postmortem muscle simultaneously under the Korean standard pre- and post-slaughter conditions. A total of 111 Yorkshire (pure breed and castrated male) pigs were evaluated under the Korean standard conditions. Measurements were taken of the levels of blood glucose and lactate at exsanguination, and muscle glycogen and lactate content at 45 min and 24 h postmortem. Certain pork quality traits were also evaluated. Correlation analysis and multiple regression analysis including stepwise regression were performed. Exsanguination blood glucose and lactate levels were positively correlated with each other, negatively related to postmortem muscle glycogen content and positively associated with postmortem muscle lactate content. A rapid and extended postmortem glycolysis was associated with high levels of blood glucose and lactate, with high muscle lactate content, and with low muscle glycogen content during postmortem. In addition, these were also correlated with paler meat color and reduced water holding capacity. The results of multiple regression analyses also showed that metabolites in exsanguination blood and postmortem muscle explained variations in pork quality traits. Especially, levels of blood glucose and lactate and content of muscle glycogen at early postmortem were significantly associated with an elevated early glycolytic rate. Furthermore, muscle lactate content at 24 h postmortem alone accounted for a considerable portion of the variation in pork quality traits. Based on these results, the current study confirmed that the main factor influencing pork quality traits is the ultimate lactate content in muscle via postmortem glycolysis, and that levels of blood glucose and lactate at exsanguination and contents of muscle glycogen and lactate at postmortem can explain a large portion of the variation in pork quality even under the standard slaughter conditions.

• The Korean Journal of Pharmacology
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• v.18 no.1
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• pp.33-41
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• 1982

In this paper, the influences of adrenergic blockades; propranolol and phenoxybenzamine on the changes of hyperglycemic action, hepatic glycogen content, and brain norepinephrine (NE) content induced by clonidine were investigated in the male mice. The results obtained were summarized as follows: 1) Blood glucose level was significantly increased by clonidine $(30{\mu}g/kg)$. The increase of blood glucose level induced by clonidine was not affect by the propranolol (10mg/kg) pretreatment, but significantly inhibited by the phenoxybenzamine (10mg/kg) pretreatment. 2) Hepatic glycogen content was moderately inhibited by clonidine. The decrease of hepatic glycogen content induced by clonidine was not affected by the propranolol and phenoxybenzamine pretreatment. 3) Brain NE content was significantly increased in 30 minutes and 60 minutes after clonidine treatment. The increase of brain NE content induced by clonidine was significantly inhibited by the phenoxybenzamine pretreatment. The increase of train NE content induced in 90 minutes and 120 minutes after clonidine treatment was more markedly increased by the propranolol pretreatment.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.55 no.1
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• pp.73-77
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• 2022

The shelf life of oysters Crassostrea gigas, in two different types of packaging containers, polyethylene (PE) and polyethylene terephthalate (PET), was determined by evaluating the pH, glycogen and soluble protein content, turbidity, and viable cell count. After 7 days of storage, the pH of the packing water in the PE container decreased to 5.88, while the pH in the PET container decreased to 6.03. In the PE container, the glycogen content of the oysters decreased by 0.85 g/100 g and the soluble protein content and turbidity of the packing seawater increased by 1,927.21 mg/100 g and 3.24 McF, respectively. In the PET container, the glycogen content of the oysters decreased by 0.96 g/100 g and the soluble protein content and turbidity of the packing seawater increased by 1,674.75 mg/100 g and 0.98 McF, respectively. The reaction rate constants (K) were as follows: glycogen content, -0.18 (PE) and -0.10 (PET); soluble protein content, 0.29 (PE) and 0.26 (PET); and turbidity, 0.41 (PE) and 0.06 (PET). These results suggested that PET can be used as a new packaging container material for raw oysters because the quality is maintained and it offers more convenient handling during distribution.

• Korean Journal of Food Science and Technology
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• v.17 no.3
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• pp.223-226
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• 1985

The taste compounds including glycogen, nucleotides and their related compounds and free amino acid content of Raw, Boiled and Sun-dried and Boided and 1lot-air dried surf clam(Mactra veneriformis) were investigated. Crude protein and crude lipid content changed little after processing, but ash content of processed surf clam was increased 21.5%. Glycogen content was increased 6.7% in a processed surf clam. In nucleotides and their related compounds there are much ATP, ADP, IMP and Hypoxannthine in raw material, ATP, ADP, IMP content was decreased and Hypoxannthine disappeared after processing, In the raw extract, glycine, alanine, arginine were abundant, holding 85% of total free amino acid contents. After processing, generally 60% of raw material free amino acids content were existed.

• The Korean Journal of Physiology
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• v.22 no.1
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• pp.63-77
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• 1988

This study was carried out to investigate relationships between maximal running time (MRT) and glycogen supercompensation in fast twitch white fibers (white vastus, WV), fast twitch red fibers (red vastus, RV) and slow twitch red fibers (soleus muscle, SM) of endurance-trained rats. Male rats of a Sprague-Dawley strain were divided into the trained groups and untrained groups. Untrained groups were acquired to run on the treadmill 10 minutes for 3 days and remained rest and maintained with mixed diet for 4 weeks. For last 10 days of resting period, the untrained rats were divided into 3 groups i.e. mixed diet (untrained control), high and low carbohydrate (CHO) diet groups. And each group was subdivided into 2 groups, one group was tested for the MRT and the other was sacrificed to measure the blood glucose, blood lactate, glycogen contents of liver and muscles. The experimental groups were trained on treadmill by a modified method of Constable et al. (1984) maintained with mixed diet for 4 weeks. After measurement of MRT of this group, they were also divided into high and low CHO groups and fed with these diet for 2 days and MRT of each group was measured again to see the effect of high or low CHO feeding on the MRT. Each group was maintained with the same diet for next 2 days during which some of the rats were sacrificed at given time intervals for the measurements of blood glucose and lactate, liver and the muscles glycogen. The results were summarized as follows; 1) In the untrained group, there were no significant differences between subgroups in MRT, glycogen conent of SM, RV and WV. But blood glucose concentration and glycogen content of liver of low CHO group were significantly lower than those of mixed diet group. 2) The MRT and glycogen content of SM, RV and WV of trained mixed diet group were significantly increased compared to those of untrained mixed diet group, but there was no significant difference in glycogen content of liver. 3) MRT of trained mixed, high CHO and low CHO groups were $137{\pm}9.8,\;176{\pm}9.8\;and\;129{\pm}7.3\;min$ respectively with the significant difference between them. 4) There were no differences in blood lactate concentrations between the trained high and low CHO groups immediately after maximal running and during recovery period. 5) Glycogen contents in RV and SM of trained high CHO group were significantly increased, and glycogen contents in RV, WV and liver of trained low CHO group were significantly decreased compared to those of trained mixed diet group. 6) Immediately after maximal running, the blood glucose concentrations of trained high CHO and low CHO groups were $73{\pm}4.0\;and\;67{\pm}6.9mg%$ respecitively. The blood glucose of the trained high CHO group was fully recovered within one hour by feeding. But blood glucose concentration of low CHO group was slowly recovered up to $114{\pm}4.1mg%$ after two hours of feeding and maintained. Those values were still significantly lower than that of trained mixed diet group. The synthetic rates of glycogen in liver and muscles during the recovery period followed the similar time course of the blood glucose recoveries in each group. These results suggest that an increase in MRT of trained high CHO group was attributed to the glycogen supercompensation in slow twitch muscle fibers. And a decrease in MRT of trained low CHO may be due to decreased glycogen contents of liver and muscles. The results also suggest that glycogen supercompensation was more evident in slow twitch red fibers of endurance-trained rats and blood glucose is one of the limiting factors of glycogen synthesis.