Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Diet and Exercise

Does size matter?

  When it comes to how blood vessels function, the answer is yes. A new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology examined this question for the first time in toads (Rhinella marina). Regulation of blood vessel diameter, and hence blood pressure, is a complex process involving a variety of factors that are secreted by cells in the vascular wall in addition to factors found […]

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Animals that eat plastic?

Have you seen this? A video just released by Yellowstone National Park talks about how some heat-loving microorganisms can break down plastics. Pretty cool.   Not so cool was the recent finding published in the Proceedings of the Royal Society B: Biological Sciences that Astrangia poculata coral polyps are eating microplastics instead of brine shrimp eggs…on purpose. In the lab, the team were able to observe the corals consuming nearly […]

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Rapid switches in metabolism of hibernating animals

  In a new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, researchers examined how changes in metabolism during torpor are regulated in 13-lined ground squirrels (Ictidomys tridecemlineatus). During hibernation, these animals cycle between bouts of torpor (about 2 weeks each) when their metabolism is reduced by 95% and body temperature can drop to 5degC and short states of interbout euthermia when both temperature […]

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Editor’s picks for 2018

The Editor’s Picks for 2018 have been released for the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology. According to the editorial team, the focus of this journal is on “the regulation of whole organismal function that requires the interplay of multiple organ and tissue systems.” The top comparative physiology articles of 2018 included: An article by Hersh et al., who provided evidence that little skates may be useful […]

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Birds have a unique way of preventing muscle wasting

Muscle wasting is a major complication associated with cirrhosis and liver failure. Normally the liver functions to convert ammonia into urea. But with liver failure, this process does not work well leading to high levels of circulating ammonia, which is thought to contribute to muscle wasting in mammals. A new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, explored whether birds have the same muscle wasting […]

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A mother’s diet can have a lasting impact on offspring

A new study published in Physiological Reports provides evidence that a mother’s diet during pregnancy could have lasting impacts on her offspring’s bone development and later risk of osteoporosis. Osteoporosis is characterized by a loss of trabecular (spongy) bone leading to increased risk for developing bone fractures.  The researchers discovered this relationship while studying female microswine that were consuming a diet containing only 1% protein late in their pregnancy and for […]

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Lactate directly increases breathing

Hypoxic environments increase ventilation in animals. This helps to bring in more oxygen when environmental levels may be limited. With limited oxygen availability, the body turns to anaerobic metabolism, resulting in the production of lactate ions. These ions are known to indirectly stimulate breathing by lowering blood pH and were more recently discovered to directly stimulate the carotid body to increase breathing. For this reason, lactate ions are thought to […]

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Highlights from EB 2019

There were so many poster presentations on comparative and evolutionary physiology today at the 2019 Experimental Biology conference that it was impossible to see them all. Here are some highlights: Dr. Michael Hedrick from California State University – East Bay, presented his research on African cheetahs (Acinonyx jubatus) examining adaptations that cheetahs have evolved to supply their muscles with oxygen so efficiently, given they maintain the world record for being […]

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Obese Horses

Abigail Harms, an undergraduate student at Beloit College working with Dr. Kathryn Johnson, also presented her research today at the Experimental Biology 2019 conference examining the effects of obesity in horses. Just like humans and pets, horses are increasingly becoming obese. Her research is seeking ways to measure hormonal changes that occur with obesity in different breeds of horses.  

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