August Krogh

Life

He was born in Grenaa on the peninsula of Djursland in Denmark, the son of Viggo Krogh, a shipbuilder. His mother (born Drechmann) was the daughter of a customs officer in Holstein. Through his mother’s family he claimed "a dash of" Romani blood https://royalsocietypublishing.org/doi/10.1098/rsbm.1950.0014. Krogh was educated at the Aarhus Katedralskole in Aarhus. He attended the University of Copenhagen graduating MSc in 1899 and gaining a doctorate PhD in 1903.

Krogh was a pioneer in comparative physiology. He wrote his thesis on the respiration through the skin and lungs in frogs: Respiratory Exchange of Animals, 1915. Later Krogh took on studies of water and electrolyte homeostasis of aquatic animals and he published the books: Osmotic Regulation (1939) and Comparative Physiology of Respiratory Mechanisms (1941). He contributed more than 200 research articles in international journals. He was a constructor of scientific instruments of which several had considerable practical importance, such as the spirometer and the apparatus for measuring basal metabolic rate.

Krogh began lecturing in the University of Copenhagen in 1908 and in 1916 was promoted to full professor, becoming the head of the first laboratory for animal physiology (zoophysiology) at the university.

Krogh was elected an International Honorary Member of the American Academy of Arts and Sciences in 1931, an International Member of the United States National Academy of Sciences in 1937, and an International Member of the American Philosophical Society in 1941.

In the 1930s, Krogh worked with two other Nobel prizewinners, the radiochemist George de Hevesy and the physicist Niels Bohr on the permeability of membranes to heavy water and radioactive isotopes, and together, they managed to obtain Denmark's first cyclotron for experiments on animal and plant physiology as well as in dental and medical work.

Foundation of Novo Nordisk

In 1922, August Krogh went on a lecture tour to North America after receiving the Nobel Prize in Physiology or Medicine. During this tour, he and his wife Marie, a doctor who was herself suffering from a type 2 diabetes, visited Toronto where the scientists Frederick Banting, Charles Best and John Macleod had just succeeded in manufacturing active insulin. Krogh received permission to manufacture insulin in the Nordic countries and joined forces with Hans Christian Hagedorn, a physician specialising in diabetes, to start the production of insulin in Denmark. This led to the establishment of Nordisk Insulinlaboratorium company in 1923.

In 1925, brothers Harald and Thorvald Pedersen, who were former employees of Nordisk, formed their own company, Novo Terapeutisk Laboratorium. Novo and Nordisk competed until they merged in 1989 to become Novo Nordisk A/S.https://www.novonordisk.com/about/our-heritage.html

Family

He married Marie Krogh (née Jørgensen, 1874–1943) in 1905. She was a renowned scientist in her own right and much of August Krogh's work was carried out in close collaboration with her.

August and Marie had four children, the youngest of whom, Bodil, was born in 1918. She too was a physiologist, and became the first woman president of the American Physiological Society in 1975. Bodil married another eminent physiologist, Knut Schmidt-Nielsen.

Legacy

Torkel Weis-Fogh, an eminent pioneer on the study of insect flight, was a student of August Krogh's. Together they wrote a classic paper on that subject in 1951.

Krogh's name is preserved in two items now named for him:

• Krogh length, the distance between capillaries which nutrients diffuse to, based on cellular consumption of the nutrients.
• Krogh's principle, that "for... a large number of problems there will be some animal of choice, or a few such animals, on which it can be most conveniently studied." He via his book, The Anatomy and Physiology of Capillaries, popularized the false belief that if you were to lay out all the blood vessels from a human body they would reach 100,000 km in length. He made false assumptions about cappilary density while also using a hypothetical body that weighed 140 kg with 50 kg of pure muscle, an unrealistic physique, to get his round figure of 100,000 km. Recent finding suggest that the actual figure is somewhere between 9,000–19,000 km.

Publications

• The Respiratory Exchange of Animals and Man (1916)
• Osmotic Regulation in Aquatic Animals (1939)
• The Comparative Physiology of Respiratory Mechanisms (1941)

References

References

1. (1950). "August Schack Steenberg Krogh. 1874-1949". [[Obituary Notices of Fellows of the Royal Society]].
2. (1950). "August Krogh". Acta Physiologica Scandinavica.
3. (1950). "Deaths of C. M. Wenyon, Clifford Dobell and A. Krogh". Comptes rendus des séances de la Société de biologie et de ses filiales.
4. (1967). "August Krogh (1874-1949) the physiologist's physiologist". JAMA: The Journal of the American Medical Association.
5. (2006). "August Krogh". Clinical Cardiology.
6. (1951). "August Krogh, November 15, 1874-September 13, 1949". The Yale Journal of Biology and Medicine.
7. "The Founders". Novo Nordisk.
8. (July 2006). "Biographical Index of Former Fellows of the Royal Society of Edinburgh 1783–2002". The Royal Society of Edinburgh.
9. (2014-09-11). "George de Hevesy: Explosion of new knowledge". Niels Bohr Institute.
10. (9 February 2023). "August Krogh".
11. "August Krogh".
12. "APS Member History".
13. "Our history".
14. "August Krogh - Facts". Nobelprize.org.
15. Dantzler, William H.. (July 2015). "Obituary Bodil Schmidt-Nielsen (1918-2015) 48th APS President".
16. ''Living history of physiology: Bodil Schmidt-Nielsen'' (Prof. William Dantzler. University of Arizona) [http://advan.physiology.org/cgi/content/full/30/1/1] {{Webarchive. link. (2008-12-26)
17. "© the American Physiological Society - Bodil M. Schmidt-Nielsen".
18. (1951). "The Respiratory Exchange of the Desert Locust (Schistocerca Gregaria) before, During and After Flight". The Company of Biologists.
19. Fournier, R. L. ''Basic Transport Phenomena in Biomedical Engineering''. Taylor & Francis, London, 1999.
20. [http://www.nature.com/nmat/journal/v6/n11/abs/nmat2022.html Choi et al. Microfluidic scaffolds for tissue engineering. Nature Materials (2007) vol. 6 pp. 908-915]
21. Bernard, Claude. ''Introduction à l'étude de la médecine expérimentale'', J.B. Baillière et Fils, Libraires de L'Académie Impériale de Médecine, 1865. pp. 400
22. (2021). "August Krogh: Muscle capillary function and oxygen delivery". Comparative Biochemistry and Physiology. Part A, Molecular & Integrative Physiology.