Rencular morphology and renal vascular system of the harbour porpoise Phocoena phocoena (L.)

The kidneys of 35 harbour porpoises, Phocoena phocoena (L.), from the western North Atlantic were studied. Kidneys are large (0.84% of body weight) and multirenculate (approximately 300 renculi per kidney). Renculi have well developed medullary papillae (71–80% of rencular thickness) which correlate...

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Bibliographic Details
Published in:Canadian Journal of Zoology
Main Authors: Hedges, N. A., Gaskin, D. E., Smith, G. J. D.
Format: Article in Journal/Newspaper
Language:English
Published: Canadian Science Publishing 1979
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Online Access:http://dx.doi.org/10.1139/z79-107
http://www.nrcresearchpress.com/doi/pdf/10.1139/z79-107
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Summary:The kidneys of 35 harbour porpoises, Phocoena phocoena (L.), from the western North Atlantic were studied. Kidneys are large (0.84% of body weight) and multirenculate (approximately 300 renculi per kidney). Renculi have well developed medullary papillae (71–80% of rencular thickness) which correlates well with an ability to produce concentrated urine. Zonation of the vascular system within the medulla is also present, another characteristic of mammals producing concentrated urine.The intrarencular vascular supply is typically mammalian and similar to other cetaceans. As a result of excellent injection techniques, we found greater complexity and variability in the vascular system in our specimens than has been previously reported.Vascular control is discussed in relation to diving bradycardia. Parasympathetic nerves may stimulate vasodilation to quickly restore rencular circulation at the end of a dive.