Experimental Biology 2011- Comparative Physiology of Brown Adipose Tissue

You may recall the previous post on the seminar that I attended on Comparative Physiology of Brown Adipose Tissue at the Experimental Biology meeting last week.

Here are some of the comparative physiology abstracts that were presented at the meeting on this topic:

-Dr. Michael Symonds and colleagues from the The University of Nottingham, United Kingdom, presented "The Use of Thermal Imaging of Brown Adipose Tissue in the Supraclavicular Region as a Repeatable Technique to Quantify its Function in Humans." Dr. Symonds presented data showing that the temperature of the brown adipose tissue in children's bodies actually increased in response to placing their hands or feet into cool water. They hope to use this thermal imaging technique to further characterize the role of brown adipose tissue in children.

In other research, Drs. Kirsi Virtanen and Pirjo Nuutila from the Turku PET Centre, Turku, Finland, have used combined PET and CT scans to demonstrate that adult human brown adipose tissue is highly active metabolically. Their studies show that this tissue actively takes up the metabolic substrate glucose when adults are exposed to cold. Figure 2 from the research paper ("Functional Imaging of Brown Adipose Tissue", Heart Metab. 2010;48:15-17) is shown below:
BAT and Cold.bmp

-Linnea Pearson (University of Alaska, Fairbanks) presented her work completed with Drs. Mike Hammill (Maurice Lamontagne Institute, Mont-Joli, QC, Canada) and Jennifer Burns (University of Alaska, Anchorage), entitled "Brown Adipose Tissue and Non-shivering Thermogenesis Aid Harp Seals (Pagophilus groenlandicus) but not hooded seals (Cystophora cristata) or Weddell Seals (Leptonychotes weddelli) at birth." Imagine being born on ice. Brrrrr!!! Baby seals, called pups, have evolved ways to stay warm under these harsh environmental conditions. According to the authors, harp and Weddell seals have thinner layers of blubber than hooded seals and have a lanugo pelage (fur) that is wetable. They found that while newborn hooded seals use thicker layers of blubber and a dense pelage to stay warm, harp seal pups use non-shivering thermogenesis whereas Weddell seals derive their warmth from heat produced through increased muscle metabolism.

Harp Seal Pup:

Hooded Seal with Pup:

Weddell Seal Pup (Photo by Joan Myers):

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