Thirst-endurance in some Vertebrates

Alimentary Systems in Some Homeothermic Vertebrates

Comparative physiology of body fluid regulation in vertebrates with special reference to thirst regulation.

The origin of life took place in the ancient sea where the ionic concentration is thought to have been somewhat lower than that of the present day seas. This may partly explain why most vertebrate species have plasma ionic concentrations roughly one-third of seawater. Exceptions are primitive marine cyclostomes whose plasma is almost identical to seawater, and marine cartilaginous fishes that a...

Some Vertebrates Go with the GLO

Most vertebrates synthesize vitamin C (ascorbate) de novo from glucose, but humans and certain other mammals cannot. In this issue, Montel-Hagen et al. (2008) demonstrate that erythrocytes from these ascorbate auxotrophs switch the preference of their glucose transporter Glut1 from glucose to dehydroascorbate (DHA), the oxidized form of vitamin C. This substrate preference switch is mediated by...

Thirst

hypothermia is an adjunct, purely a "metabolic crutch, providing additional time in which to pursue the specific treatment, whether medical or surgical." The pathophysiology of the major congenital and acquired cardiac lesions is discussed in terms of the applicability and usefulness of hypothermia. In addition, the author discusses and evaluates the varied clinical situations in which hypother...

Thirst

Our bodies are mostly water, and this water is constantly being lost through evaporative and other means. Thus the evolution of robust mechanisms for finding and consuming water has been critical for the survival of most animals. In this Primer, we discuss how the brain monitors the water content of the body and then transforms that physical information into the motivation to drink.