Is the polar bear (Ursus maritimus) a Hibernator?: continued studies on opioids and hibernation

@article{Bruce1990IsTP,
  title={Is the polar bear (Ursus maritimus) a Hibernator?: continued studies on opioids and hibernation},
  author={David Stewart Bruce and Nancy K. Darling and Katheleen J. Seeland and Peter R. Oeltgen and Sita P. Nilekani and Steven C. Amstrup},
  journal={Pharmacology Biochemistry and Behavior},
  year={1990},
  volume={35},
  pages={705-711}
}
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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.
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References

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Behavior, Biochemistry, and Hibernation in Black, Grizzly, and Polar Bears
Annual behavioral and biochemical patterns of black bears (Ursus americanus), grizzly bears (Ursus arctos horribilis), and polar bears (Ursus maritimus) were reviewed. We propose that black and
Midsummer observations on the behavior of wild polar bears (Ursus maritimus)
TLDR
A diurnal rhythm was recorded in which bears slept most during the latter third of the 24-h cycle and least in the first third, and all cubs observed hunted, but they exhibited great variety in patience and apparent skill.
IMMOBILIZATION OF POLAR BEARS (URSUS MARITIMUS PHIPPS) WITH A MIXTURE OF TILETAMINE HYDROCHLORIDE AND ZOLAZEPAM HYDROCHLORIDE
TLDR
Preliminary results indicated that the bears did not suffer respiratory depression and were able to thermoregulate while immobilized and could be handled safely while under the effects of the drug and workers could readily evaluate the state of their sedation by their reactions.
The significance of supplemental food to polar bears during the ice-free period of Hudson Bay
TLDR
The data indicated that individual needs and learning were major factors determining which bears used the Churchill dump, and bears which fed in the dump were significantly heavier than those which did not.
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