Gluconeogenesis in arctic ground squirrels between periods of hibernation.

@article{Galster1975GluconeogenesisIA,
  title={Gluconeogenesis in arctic ground squirrels between periods of hibernation.},
  author={W. A. Galster and Peter R. Morrison},
  journal={The American journal of physiology},
  year={1975},
  volume={228 1},
  pages={
          325-30
        }
}
The hibernation season in the arctic ground squirrel (Citellus undulatus) is broken into 8- to 18- day cycles by short homeothermal periods during which the carboydrate reserves depleted during hibernation are replenished. This study follows a number of metabolities in tissues and body fluids to assess the sources for reconstitution of the glucose reserves: lactate, urea, ammonia, free fatty acid, glycerol, triglyceride, and glucose in plasma; glycogen in liver and muscle; and urea and ammonia… Expand
Seasonal activity patterns of glycolytic enzymes in a hibernator, the Arctic ground squirrel Spermophilus parryi
TLDR
The enzyme activities in skeletal muscle changed in seemingly disparate ways with some enzymes increasing in hibernation, while others decreased, and yet others remained unchanged, in the light of the hibernating habit of the mammal. Expand
Urea-hydrolysis in euthermic hibernators and non-hibernators during periods of food availability and deprivation
TLDR
There did not appear to be a correlation between an animal's ability to hibernate and to expire 14 CO 2 from hydrolyzed 14 C-urea injected intraperitoneally and it is speculated that urea hydrolysis may be more directly related to gut bacterial biomass or pH regulation during protein catabolism. Expand
Liver energy metabolism during hibernation in the golden-mantled ground squirrel, Spermophilus lateralis
TLDR
It is shown that total extractable liver [ATP], [ADP], and [ ATP]/[ADP] do not differ among summer normothermic, hibernating, and aroused golden-mantled ground squirrels, Spermophilus lateralis, indicating that metabolism remains well balanced throughout the hibernation cycle. Expand
Metabolic cycles in a circannual hibernator.
TLDR
This finding provides new data that strongly support the predictions of a long-standing hypothesis that periodic arousals are necessary to restore metabolic homeostasis in ground squirrels. Expand
Nitrogen recycling buffers against ammonia toxicity from skeletal muscle breakdown in hibernating arctic ground squirrels
TLDR
Evidence of increased myofibrillar (skeletal muscle) protein breakdown and suppressed whole body production of metabolites in vivo throughout deep torpor is shown and the orchestration of metabolic pathways that sustain the provision of essential and non-essential amino acids and prevent ammonia toxicity during hibernation is illustrated. Expand
Metabolic Rate and Prehibernation Fattening in Free-Living Arctic Ground Squirrels
TLDR
It is found that arctic ground squirrels do not trade off metabolism to facilitate rates of weight gain before hibernation, but they do use energy sparing strategies before hiberration that help maintain peak mass. Expand
Metabolism of hepatocytes from a mammalian hibernator, Spermophilus lateralis
TLDR
This unique metabolice organization may permit energetic savings by allowing for a reduced Vb2 in deep hibernation, and an elevated VO2 during arousal to support high biosynthesis rates, thereby minimizing arousal durations and their attendant thermogenic demands. Expand
Carbohydrate and torpor duration in hibernating golden-mantled ground squirrels (Citellus lateralis)
TLDR
It was found that plasma glucose depletion is not the stimulus for arousal in torpid C. lateralis, and plasma glucose and hepatic and skeletal muscle glycogen remain stable during torpor in this species, in marked contrast to the carbohydrate depletion reported for Citellus undulatus. Expand
Hibernation-hypothermia and metabolism in hedgehogs. Changes in some organic components.
  • K. S. Al-Badry, H. Taha
  • Biology, Medicine
  • Comparative biochemistry and physiology. A, Comparative physiology
  • 1983
TLDR
The nature of the biochemical changes that occurred throughout the hibernation cycle implies that metabolism in hedgehogs is influenced by dynamically balanced control mechanisms operating within a wide range of temperatures. Expand
Regulation of Skeletal Muscle Carbohydrate Metabolism During Mammalian Hibernation
Thirteen-lined (Ictidomys tridecemlineatus) and Richardson’s (Urocitellus richardsonii) ground squirrels survive harsh winter conditions by entering hibernation, spending the majority of their timeExpand
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Hibernation and arousal were associated with significantly increased hepatic and renal lactic dehydrogenase and hepatic glutamic-oxaloacetic transaminase activities but glucose-6-phosphatase and fructose-1,6-diphosphat enzyme activities remained unchanged. Expand
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