Life Lines by Dr. Dolittle

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Tag Archive for ‘fish’

Breathing air

Researchers interested in the evolution of air breathing in bony fishes (Osteicthyes) recently published a fascinating review in the Physiologist. The ability to breathe air made life on land as we know it possible. What is interesting though is that the ability to breathe air actually evolved independently possibly 38-67 times in history. Currently, there are over 400 air-breathing fishes belonging to the Sarcopterygii and Actinopterygii classes. To adapt to life on land, […]

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Importance and dangers of oxygen for air-breathing animals

Although oxygen is essential for air-breathing species and allowed for the evolution of multicellular organisms, it is also a dangerous molecule that can lead to cellular toxicity through the generation of reactive oxygen species (ROS). However, it is important to point out that cellular ROS also play several physiological roles in the body. I just read an interesting review article published in Physiological Reviews that explored natural oxygen delivery and availability […]

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Fish offer clues to fixing broken hearts

About a year ago we talked about how Mexican tetra (Astyanax mexicanus) may hold the clues to treating diabetes. New research shows that is not all these tiny fish can teach us. Researchers at the University College London and the University of Oxford now think these fish may hold clues to regenerating damaged heart tissue. Their findings were published in Cell Reports. Mexican tetra are freshwater fish. Over millions of years, […]

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Compromising fish

Here’s something to think about. How do fish optimize gas exchange in their gills to efficiently take up oxygen (favoring large, thin, permeable membranes) while at the same time limiting water and ion movement across the surface? If they reduce surface area, then oxygen transfer will be limited, but ions and water transfer will be optimized. What is a fish to do? A new review article published in Physiology discussed how […]

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Hypoxia and anoxia and reoxygenation, Oh my!

There are many examples of animals that can naturally tolerate hypoxic and anoxic conditions without exhibiting pathologies associated with reoxygenation. Here are a few examples from this year’s conference: Dr. Anthony Signore (University of Nebraska) spoke about how some hypoxia tolerant animals can use carbon monoxide, you know that gas we think of as poisonous, to improve oxygen binding to hemoglobin in hypoxic conditions. Well known for their ability to […]

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How Animals Deal with Stress

  Victor Zhang (Graduate Student working with Dr. Loren Buck at Northern Arizona University) gave an interesting talk on his research to measure stress and activity patterns in free living arctic ground squirrels. They found overall that females were less stressed than males although stress levels and activity varied during lactation. I think some human mothers can agree with those observations. Oliver Wearing (Graduate student working with Dr. Graham Scott […]

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