August Krogh
Oxford Dictionary of Scientists:
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Schack August Steenberg Krogh
Danish physiologist (1874–1949)
Krogh, the son of a brewer from Grenaa in Denmark, was educated at the Aarhus gymnasium and the University of Copenhagen, where he obtained his PhD in 1903. He spent his whole career at the university, serving as professor of animal physiology from 1916 until his retirement in 1945.
Krogh first worked on problems of respiration. He argued, against his teacher Christian Bohr, that the absorption of oxygen in the lungs and the elimination of carbon dioxide took place by diffusion alone. He made precise measurements to show that the oxygen pressure was always higher in the air sacs than in the blood and, consequently, there was no need to assume any kind of nervous control.
It was, however, with his studies of the capillary system that Krogh achieved his most dramatic success. The simplest explanation of its action was to assume it was under the direct hydraulic control of the heart and arteries: the stronger the heart beat, the greater the amount of blood flowing through the capillaries. Krogh had little difficulty in showing the inadequacy of such a scheme by demonstrating that even among a group of capillaries fed by the same arteriole some were so narrow that they almost prevented the passage of red cells while others were quite dilated, allowing the free passage of the blood. Not content with this descriptive account Krogh went on to make a more quantitative demonstration. Working with frogs, which he injected with Indian ink shortly before killing, he showed that in sample areas of resting muscle the number of visible (stained) capillaries was about 5 per square millimeter; in stimulated muscle, however, the number was increased to 190 per square millimeter. From this he concluded that there must be a physiological mechanism to control the action of the capillaries in response to the needs of the body. It was for this work, fully described in The Anatomy and Physiology of Capillaries (1922), that Krogh was awarded the 1920 Nobel Prize for physiology or medicine.
Gale Encyclopedia of Biography:
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Schack August Steenberg Krogh
The Danish physiologist Schack August Steenberg Krogh (1874-1949) is noted for his classic researches on the anatomy and physiology of the blood capillaries and his contributions to respiratory physiology, marine biology, and cell physiology.
August Krogh was born on Nov. 15, 1874, in Grenaa, Jutland. As a boy, he read widely in botany, zoology, physics, and chemistry, but he was uncertain at first whether to specialize in physics or zoology. He attended lectures on medical physiology by Christian Bohr, father of the physicist Niels Bohr, and decided forthwith to follow a career in physiology. In 1899 Krogh was appointed assistant in Christian Bohr's laboratory, and in 1903 he received a doctorate for his analysis of respiratory exchanges of oxygen and carbon dioxide in the lung and skin of frogs.
With his own new methods Krogh extended his studies of respiration to other animals, including man. At the time he started research, it was thought that the lung secreted oxygen into the bloodstream. In 1910, when his famous seven papers on the mechanism of gas exchange appeared, Krogh could state beyond doubt, "The absorption of oxygen and elimination of carbon dioxide in the lungs takes place by diffusion and by diffusion alone." In 1908 he was made head of his own Zoophysiological Laboratory, first as dozent and then in 1916 as professor of zoophysiology in the University of Copenhagen. This laboratory and a still larger one, built in 1926 for him and to his own detailed specifications, became world-famous research centers, attracting students from far and near.
Beginning in 1915, Krogh turned his attention to the mechanisms by which blood capillaries supply oxygen to muscle cells and remove carbon dioxide in the large volumes demanded by exercise. His hypothesis of metabolically controlled, intermittent opening of capillary blood vessels led to experiments for which he received the Nobel Prize in 1920 and to a monograph entitled The Anatomy and Physiology of the Capillaries. This book still has unprecedented influence on medical research because of its implications for cell metabolism, water balance, inflammation, and disease.
Throughout his life Krogh maintained a knowledge of physics and physical chemistry rarely attained by biologists of the time. He also had a brilliant, intuitive perception of physical conditions, especially in microscopic dimensions. His ingenuity extended to the development of quantitative micromethods and inexpensive apparatus especially suited to each research project. Between other studies he returned repeatedly to earlier interests in marine biology, insect physiology, and osmotic relationships in plants and animals. As soon as isotopes became available, he studied diffusion and ion-pump mechanisms across membranes of single cells. Retirement from the university in 1945 meant merely the transfer of research and writing to his home laboratory.
After a brief illness August Krogh died on Sept. 13, 1949. The versatility and originality of his contributions to the life sciences, together with his scores of devoted students, place Krogh among the topmost few who produced the unprecedented growth of biology, physiology, and scientific medicine during the first half of the 20th century.
Further Reading
A 30-page memoir by P. Brandt Rehberg serves as a preface to the 1959 reprint of Krogh's The Anatomy and Physiology of the Capillaries. That volume also contains Krogh's last published paper, "Reminiscences of Work on Capillary Circulation," a lecture given in 1946 at Harvard Medical School.
Additional Sources
Schmidt-Nielsen, Bodil, August and Marie Krogh: lives in science, New York: American Physiological Society, 1995.
Columbia Encyclopedia:
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Schack August Steenberg Krogh
Krogh, Schack August Steenberg (shäk ou'gʊst stān'bĕrg krôkh), 1874-1949, Danish physiologist. He taught at the Univ. of Copenhagen (1916-45) and studied respiration, circulation, and the effect of an exclusive meat diet on the Eskimo and of deep-sea conditions on living organisms. For his discovery of the regulation of the vasomotor mechanism of the capillaries he received the 1920 Nobel Prize in Physiology or Medicine. His writings include The Anatomy and Physiology of Capillaries (1922, rev. ed. 1959), Osmotic Regulation in Aquatic Animals (1939), and Comparative Physiology of Respiratory Mechanisms (1941).
(krôg, krôKH), (Schack) August Steenberg 1874–1949.
Danish physiologist. He won a 1920 Nobel Prize for the discovery of the regulation of the capillaries' motor mechanism.
Wikipedia on Answers.com:
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August Krogh
| August Krogh | |
|---|---|
 August Krogh |
|
| Born | November 15, 1874 |
| Died | September 13, 1949 |
| Nationality | Danish |
| Fields | Zoophysiology |
| Institutions | University of Copenhagen Duke University |
| Known for | Krogh Principle[1] |
| Notable awards | Nobel Prize in Physiology or Medicine |
Schack August Steenberg Krogh FRS[2] (November 15, 1874 – September 13, 1949) was a Danish professor at the department of zoophysiology at the University of Copenhagen from 1916-1945.[3][4][5] He contributed a number of fundamental discoveries within several fields of physiology, and is famous for developing the Krogh Principle.[6][7][8]
In 1920 August Krogh was awarded the Nobel Prize in Physiology or Medicine for the discovery of the mechanism of regulation of the capillaries in skeletal muscle.[9][10] Krogh was first to describe the adaptation of blood perfusion in muscle and other organs according to demands through opening and closing the arterioles and capillaries.
Krogh was a pioneer in comparative studies on animals. 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). In addition Krogh contributed more than 200 research articles in international journals. He was a constructor of scientific instruments of which several had considerable practical importance, e.g. the spirometer and the apparatus for measuring basal metabolic rate.
Krogh brought insulin to Denmark shortly after its discovery in 1922 by Nicolae Paulescu.[citation needed] Together with Hagedorn, Krogh made decisive contributions to establishing a Danish production of insulin by ethanol extraction of the hormone from the pancreatic glands of pigs.[citation needed]
Much of Krogh's work was carried out in collaboration with his wife, Marie Krogh (1874–1943), a renowned scientist in her own right.
In 1910 August Krogh founded the first laboratory for animal physiology (zoophysiology) at the University of Copenhagen.[chronology citation needed] It was located in a small townhouse in central Copenhagen (at Ny Vestergade 11). The laboratory was considerably enlarged in 1928, when it moved to a new building at Juliane Maries Vej 28-32 called The Rockefeller Complex (it was financed by the Rockefeller Foundation).[chronology citation needed] The building also gave place to the institutes of medical physiology and biophysics, and to the institute for the theory of gymnastics (exercise physiology). Today, the disciplines of animal physiology, exercise physiology, and some of the biochemical subdisciplines under the Faculty of Science are based at the August Krogh Institute, a building inaugurated in 1970.[chronology citation needed] August and Marie had four children, the youngest of whom, Bodil, was born in 1918.[chronology citation needed] Bodil married an eminent physiologist, Knut Schmidt-Nielsen, in 1939 and had three children.[chronology citation needed] She received her Dental degree in 1941, was the first recipient of a Doctor in Odontology in 1946, and her PhD in 1955, all from the University of Copenhagen.[chronology citation needed] Knut and Bodil moved to America and each had independently prominent physiology careers at prestigious universities, including Duke University, and were well known for their many students who became leaders in the field.
Torkel Weis-Fogh, an eminent pioneer on the study of insect flight, was a student of August Krogh's.
(description partly taken from Copenhagen University)
See also
References
- ^ Krebs, H. A. (1975). "The August Krogh principle: "For many problems there is an animal on which it can be most conveniently studied"". Journal of Experimental Zoology 194 (1): 221–226. DOI:10.1002/jez.1401940115. PMID 811756.
- ^ Hill, A. V. (1950). "August Schack Steenberg Krogh. 1874-1949". Obituary Notices of Fellows of the Royal Society 7 (19): 220. DOI:10.1098/rsbm.1950.0014.
- ^ Drinker, C. K. (1950). "August Krogh: 1874-1949". Science 112 (2900): 105–107. DOI:10.1126/science.112.2900.105. PMID 15442251.
- ^ Liljestrand, G. (1950). "August Krogh". Acta Physiologica Scandinavica 20 (2–3): 109–116. DOI:10.1111/j.1748-1716.1950.tb00688.x. PMID 15413515.
- ^ "Deaths of C. M. Wenyon, Clifford Dobell and A. Krogh". Comptes rendus des seances de la Societe de biologie et de ses filiales 144 (3–4): 160–161. 1950. PMID 15420871.
- ^ "August Krogh (1874-1949) the physiologist's physiologist". JAMA: the Journal of the American Medical Association 199 (7): 496–497. 1967. PMID 5335475.
- ^ Hurst, J. W.; Fye, W. B.; Zimmer, H. G. (2006). "August Krogh". Clinical Cardiology 29 (5): 231–233. DOI:10.1002/clc.4960290514. PMID 16739398.
- ^ Rehberg, P. B. (1951). "August Krogh : November 15, 1874—September 13, 1949". The Yale journal of biology and medicine 24 (2): 83–102. PMC 2599127. PMID 14901880. //www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2599127.
- ^ Larsen, E. H. (2007). "August Krogh (1874-1949): 1920 Nobel Prize". Ugeskrift for laeger 169 (35): 2878. PMID 17877986.
- ^ Sulek, K. (1967). "Nobel prize for August Krogh in 1920 for his discovery of regulative mechanism in the capillaries". Wiadomosci lekarskie (Warsaw, Poland : 1960) 20 (19): 1829. PMID 4870667.
External links
- Larsen, E. H. (2001). "August Krogh and the laboratory of animal physiology situated at Ny Vestergade 11". Ugeskrift for laeger 163 (51): 7240–7248. PMID 11797555.
- Kardel, T. (1999). "About the seven little devils who changed physiology. August and Marie Krogh on pulmonary gas exchange". Ugeskrift for laeger 161 (51): 7112–7116. PMID 10647306.
- Schmidt-Nielsen, B. (1984). "August and Marie Krogh and respiratory physiology". Journal of applied physiology: respiratory, environmental and exercise physiology 57 (2): 293–303. PMID 6381437.
- Poulsen, J. E. (1975). "The impact of August Krogh on the insulin treatment of diabetes and our present status". Acta medica Scandinavica. Supplementum 578: 7–14. PMID 1098401.
- Dejours, P. (1975). "August Krogh and the physiology of respiration". Scandinavian journal of respiratory diseases 56 (6): 337–346. PMID 769148.
- Kenez, J. (1965). "The Capillaries and Krogh". Orvosi hetilap 106: 177–178. PMID 14275297.
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