Licht-im-Terrarium: Literaturdatenbank
Licht-im-Terrarium: Literaturdatenbank |
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Ferguson, G. W., Gehrmann, W. H., Karsten, K. B., Hammack, S. H., McRae, M., & Chen, T. C., et al. (2003). Do panther chameleons bask to regulate endogenous vitamin d3 production? Physiological and Biochemical Zoology, 76(1), 52–59. Added by: Sarina (16/12/2008, 20:27) |
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| Resource type: Journal Article BibTeX citation key: Ferguson2003 View all bibliographic details  |
Categories: Englisch = English Keywords: Echsen = Lizards, Sehvermögen = Visual Perception, Ultraviolett = Ultraviolet, Vitamin D = Vitamin D Creators: Chen, Ferguson, Gehrmann, Hammack, Holick, Karsten, Lung, McRae Collection: Physiological and Biochemical Zoology |
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| Abstract |
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Basking by ectothermic vertebrates is thought to have evolved for thermoregulation. However, another beneficial effect of sunlight exposure, specifically the ultraviolet B (UV-B) component, includes endogenous production of vitamin D3. In the laboratory, panther chameleons exhibited a positive phototaxis to greater visible, ultraviolet A (UV-A) and UV-B light. However, with equivalent high irradiances of UV-A or UV-B, their response to UV-B was significantly greater than it was to UV-A. Exposure of in vitro skin patches of panther chameleons to high UV-B (90 μW/cm2) for 1 h significantly enhanced vitamin D3 concentration. Voluntary exposure to higher UV-B irradiance (70 vs. 1 μW/cm2) resulted in greater circulating 25-hydroxyvitamin D3 in female panther chameleons (604 vs. 92 ng/mL). Depending on dietary intake of vitamin D3, chameleons adjusted their exposure time to UV-B irradiation as if regulating their endogenous production of this vital hormone. When dietary intake was low (1–3 IU/g), they exposed themselves to significantly more UV-producing light; when intake was high (9–129 IU/g), they exposed themselves to less. Vitamin D3 photoregulation seems to be an important additional component of the function of basking.
Added by: Sarina |