State of Body Constituents

Perhaps the most remarkable result obtained in the study of the application of labeled phosphoms and of other radioactive and stable (see Schoenheimer, 160) indicators is the discovc ry of the dynamic state of the body constituents. The molecules constituting the plant or animal organism are incessantly renewed. In the course of this renewal, not only the atoms and molecules taken up with the food participate, but atoms and molecules located in one organ or in one typo of molecule will soon be found in another organ or in another type of molecule present in the same or in 

There are indications that, in the growing organism, the rate of new formation of molecules is appreciably greater than in a fully grown organism. It was found, for example, that in the liver of four-day old rats beside an appreciable formation of additional desoxyribonucleic acid, a very appreciable renewal of old molecules takes place as well. The turnover of desoxyribonucleic acid in the liver of four-day old rats is about twenty times more rapid than the corresponding value found for fully grown rats (3). 

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Schoenheimer, R. (1942). The Dynamic State of Body Constituents. (Republished 1964). Hafner Publishing, New York. 

Schoenheimer, R. The Dynamic State of Body Constituents. Cambridge, Mass. Harvard University Press, 1949. [This small book is based on lectures given at Harvard in 1941, just before Schoenheinier s death in September of that year. Although this book is out of date, it still makes very interesting reading.] ... 

Schoenheimer, R. The Dynamic State of Body Constituents Harvard... 

In 1913, George Hevesy introduced the use of radioactive indicators when he used radioactive lead to track the movement of lead from the soil into plants and then back to the soil. He later extended these studies to living animals. In 1935, he showed how elements and molecules are taken up and released continually by living cells, a process called the dynamic state of body constituents. 

The term atomic medicine was used for decades after the end of World War II to describe the new field of medicine based on the use of radioactive tracers to examine the dynamic state of body constituents. 

R. Schoenheimer, in Dynamic State of Body Constituents (Harvard University Press, (Cambridge, 1946) p. 3. 

Stetten, D., Jr., and Schoenheimer, R., J. Biol. Chem. 133, 329 (1940). Schoenheimer, R., The Dynamic State of Body Constituents. Harvard University Press, Cambridge, Massachusetts, 1942. 

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