The ability to regulate body temperature is critical for animals. This is especially true for small mammals as they have a larger surface area resulting in more heat loss to the environment than larger animals. Animals that stay active during the winter likewise have to spend more energy to stay warm. To do this well, they need to balance heat loss with heat generation through shivering as well as non-shivering […]
Phoenixin-20 is a small peptide that has been detected in mammals, birds, amphibians and fish. Studies have shown that it can modify reproductive processes in female mammals and fish. In addition, it has been shown in mammalian studies to act as a pain reducer and modulator of food intake. In a new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, researchers explored whether phoenixin-20 has […]
I just read an interesting article on the physiology of long-lived species that was published in Physiology. Some animals seem to have discovered the secret to the fountain of youth. Take the long-lived naked mole rat (Heterocephalus glaber) for example. These animals are able to maintain juvenile traits across their lifespan by growing slowly, having low levels of hormones responsible for development and delaying the onset of sexual maturity. Dwarf […]
Animals that develop within an egg, must rely on the egg yolk for nutrition for healthy development. While we have known that proteins and fats in the egg are important for development, the role of carbohydrates in the development of molluscs is a bit vague. A new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology examined the role of carbohydrates in the development of Pacific […]
Researchers at the University of Saskatchewan in Canada compared how pigs and fish absorb glucose (i.e. sugar) from the diet. They did this by measuring how well glucose moves across the intestinal wall. Their findings appear in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology. Transport of dietary glucose from the gut to the blood is facilitated by glucose transporters that pick up glucose and move it […]
Ever wonder how baleen whales (Mysticeta) get enough to eat? The mechanism is described for rorqual whales (Balaenopteridae) in a review article published this past October in Physiology. Researchers have found that rorqual whales (ex: blue whales and fin whales), in particular, have an interesting strategy for foraging. The process includes 5 steps that take place in rapid succession (about 20-90 sec total): quick forward lunges toward prey; opening their […]
Researchers at Columbia University wanted to examine whether low-calorie sweeteners disrupt glucose tolerance as there are conflicting reports in both human and animal studies. Their results examining the link between low-calorie sweeteners and glucose regulation in mice are published in the upcoming issue of the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology. In their first experiment, the research team found no differences in glucose tolerance or body […]
While egg yolks are rich in lipids, chicks consume mainly carbohydrates after hatching. This ability to switch between using nutrients provided by the mother in the egg and those the chick must acquire from the environment is important for the normal growth and metabolism of the birds after hatching. Delayed access to foods after hatching can therefore have long term effects on the animals. Transport of animals from hatcheries to […]
Adult fish rely on gills to extract oxygen from the surrounding water. Larval fish, on the other hand, do not have well-developed gills and instead rely primarily on gas exchange across their skin. In a new study published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology, researchers examined whether larval fish could use their pectoral fins to increase the flow of water […]
We have talked several times about the long-lasting issues related to growth restriction of a fetus during pregnancy: Intrauterine growth restriction increases risk of cardiovascular disease as adults Intrauterine growth restriction increases risk of insulin resistance as adults It can also result in offspring that have smaller muscles. New research published in the American Journal of Physiology – Regulatory, Integrative and Comparative Physiology suggests this may be due to adaptations to […]
Life Lines by Dr. Dolittle 