Life Lines by Dr. Dolittle

Sponsored by the American Physiological Society

Tag Archive for ‘stress’

Adapting to rising temperatures

In a new review article published in Physiology, Dr. Jonathon Stillman from San Francisco State University explores how populations of animals and humans may respond to increasing frequency of heat waves. According to Dr. Stillman, the past decade has produced some of the hottest years on record, resulting in the loss of human and animal life. Both the length and intensity of these heat waves are expected to increase, which […]

Continue Reading →

Lack of sleep stresses out birds too

Birds show signs of stress resulting from sleep loss. A new study published in Physiological and Biochemical Zoology shows that zebra finches who are sleep deprived have increased expression of inflammatory genes in their fat tissues, spleen and hippocampus region of the brain along with  increased levels of circulating stress hormones. The hippocampus is the region of the brain associated with long term memory formation. I wonder if sleep deprived birds are […]

Continue Reading →

Porcine adaptation to heat stress

  A new study published in American Journal of Physiology – Regulatory, Integrative and Comparative Physiology explored the effects of modest heat stress (35°C, 95°F) on the physiology of pigs. The found that pigs exposed to heat stress ate less than those exposed to ambient temperatures. I understand. I eat less when it is hot outside too. Since skeletal muscle is such a large metabolically active tissue, things that alter muscle metabolism […]

Continue Reading →

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 […]

Continue Reading →

New study shows mussels are “hot and bothered”

Freshwater organisms are especially vulnerable to environmental changes as they are exposed to both atmospheric changes as well as run-off from nearby cities; in particular, rising temperatures and increasing carbon dioxide levels from both natural factors (rainfall, geology, etc) as well as human influence (deforestatin, agriculture, urbanization). For example, studies of rivers around the world have found that carbon dioxide levels vary from 647 – 38,000 µatm. Higher levels are […]

Continue Reading →

Understanding stress-induced miscarriage and premature delivery

  Stress during late pregnancy may result in premature delivery or stillbirth. A new study of pregnant Rambouillet cross ewes, published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, was designed to understand why lambs succumb to stress late in pregnancy. They found that while arterial blood pressure and heart rates were normal during late gestation (final 2 weeks before birth) in fetuses from pregnant ewes with elevated stress hormones, fetal heart rate and aortic blood pressure declined on the day […]

Continue Reading →

Chronic stress causes muscle loss

Researchers have known that chronic stress has many negative health effects that can impair normal growth. The impact of stress on skeletal muscle specifically is less understood. For this reason, researchers at Universidad Andres Bello in Chile explored the effects of stress induced by overcrowding in fine flounders (Paralichthys adspersus). Their results were published this month in American Journal of Physiology – Regulatory, Integrative and Comparative Physiology.  After just four weeks of […]

Continue Reading →