Fenn, Wallace Osgood
FENN, WALLACE OSGOOD
(b.Lanesboro, Massachusetts, 27 August 1893; d.Rochester, New York, 20 September 1971)
The second of five children of William Wallace Fenn, a Unitarian minister who after 1900 was Bussey professor of theology at Harvard, and of Faith Huntington Fisher, Fenn expected to follow his father’s career until he was diverted to physiology as an undergraduate at Harvard. There he received the A.B. (1914), the A.M. (1916), and, after a year (1917–1918) in the army as a camp nutrition officer, the Ph.D. (1919), with a dissertation in plant physiology on colloid chemistry and the problems of salt antagonism. In September 1919 he married ClaraBryce Comstock; they had two sons and two daughters. From 1919 until 1922 he was instructor in applied physiology at Harvard. where his studies of phagocytosis showed that leukocytesingest carbonparticles more readily than quartz particles, a finding that clarified the pathogenesis of pulmonary stilicosis. As a traveling fellow of the Rockefeller Institute for Medical Research between 1922 and 1924, Fennstudied in England, principally in the laboratory of Archibald Vivian Hill. In 1924 he joined the newly created University of Rochester School of Medicineand Dentistry as professor and chairman of the department of physiology; he held both posts until 1959, continued as professor until 1961, and fromthen until his death was distinguished universityprofessor of physiology. Fenn was elected to the National Academy of Sciences in 1943 and to the American Academy of Arts and Sciences in 1948.
When Fenn arrived in Hill’s laboratory in 1922, he began working on muscle physiology, extending the research program for which Hill received the Nobel Prize in that year. Using measurements of heat produced by a contracting frog muscle, Fennfound in 1923 that when a muscle shortens, it liberates more energy than during an isometric contraction. This extra energy production, moreover, is proportional to the work done in shortening. These observations suggested that muscle shortening is an active process, not a passive one like the shortening of a prestretched spring, and what Hill termed the Fenn effect brought the young physiologist to prominence.
After moving to Rochester, Fenn continued the work he had started under Hill’s guidance. Earlyin the 1930’s he took measurements from high-speed motion pictures of sprint runners to assess the work performed. He also used measurements made on isolated muscles lifting different loads in the laboratory to establish the relationship between muscle force and the speed of shortening, and the nonlinear force-velocity curve for muscle he described in 1935 supported his earlier contention that muscle cannot be regarded simply as an elastic body. However, from the time of his return to the United States in 1924, Fenn’s most vigorous research program focused on muscle metabolism. In particular he investigated oxygen consumption in muscle and nerve during stimulation and recovery and in 1926 demonstrated that the conduction of a nerve impulse is accompanied by an increase in oxygen uptake, which he quantified in 1927. Similar studies on contracting muscle drew Fenn’s attention to the relationship between oxygen consumption and electrolyte levels and to the role of electrolytes in muscle and nerve functioning.
The investigations of electrolyte metabolism that ensued between 1933 and 1941 marked perhaps the most productive phase of Fenn’s research career. It was generally recognized that muscle is rich in potassium, which Fenn showed can pass through the cell membrane. By 1935 his experiments demonstrated that muscle. when it is stimulated, loses intracellular potassium and gains sodium, changes reversed in recovery. To explain this electrolyte exchange, in 1936 Fenn suggested that the loss of potassium from muscle during activity represents an increase in the permeability of the muscle membrane that permits sodium, but not chloride, to enter, This sodium, he further proposed, displaces an equivalent amount of potassium. Fenn went on to suggest in 1939 that the lost potassium tends to follow the carbohydrate cycle from muscle to liver and back again, and elucidated the mechanism bywhich potassium is reconcentrated in muscle during recovery. After radioactive potassium became available, Fenn used it in 1941 to show further the permeability of cells to potassium. His observations on potassium-sodium exchange during muscle contraction established the foundation for the later understanding of the initiation and propagation of nerve and muscle impulses.
World War II abruptly curtailed Fenn’s research program, and although he returned briefly to electrolyte physiology in the late 1950’s he did little further research on muscle physiology, Instead, starting in 1941, Fenn directed his efforts to problems of respiratory physiology of interest to the U.S. Air Force. He took up the problem of pressure breathing, a method for increasing altitude tolerance in nonpressurized airplanes by pressurizing an aviator’s lungs to raise the partial pressure of oxygen. To simulate high-altitude conditions, he built a lowpressure chamber. The concepts Fenn developed for dealing with the pressure breathing problem and for displaying graphically the relationships involved were important for respiratory physiology in general, particularly his 1946 descriptions of the pressurevolume diagram of the thorax and lungs and the oxygen-carbon dioxide diagram of the composition of alveolar air. Fenn’s group at Rochester continued to work on respiratory physiology under government contract after the war, and Fenn’s study of airway resistance helped him describe the mechanics and work of breathing in 1951. He continued to investigate respiratory physiology for the rest of his life.
From the mid 1950’s through the 1960’s Fenn became increasingly concerned with the standing and integrity of physiology as a discipline. He celebrated the growing calls that government made on physiologists during and after the war as evidence that physiology had “found recognition for itself in the marketplace,” but lamented its low prestige compared with the physical sciences. Fenn had been an active leader in the American Physiological Society since 1933, and in the International Union of Physiological Sciences since 1956. In the 1960’s he underscored the significance of such organizations to the discipline by writing on their history. His role as a spokesperson for American physiology, sustained by the many awards and honors he received, allowed less time for research.Nevertheless. by the late 1950’s work on aviation physiology had led Fenn to important research on the biological effects of extreme pressure conditions, especially on the ocean floor and in space. From 1962 to 1966 Fenn was founding director of the University of Rochester’s Space Science Center, and until the end of his life he vigorously proselytized the promise of the space program for biological research.
1. Original Works.Lists of some 267 published works authored or coauthored by Fenn are in Rahn’s biographical memoir and Dustan’s In Memoriam (see below). Fenn’s books include History of the American Physiological Society….1937–1962 (Washington, D.C., 1963). Amongthe most significant of his scientific papers are “A Quantitative Comparison Between the Energy Liberated and the Work Performed by the Isolated Sartorius Muscle of the Frog,” In Journal of Physiology, 58 (1923), 175–203; “Muscular Force at Different Speeds of Shortening,” ibid.. 85 (1935), 277–297, with B.S. Marsh; “Electrolyte Changes in Muscle During Activity,” in American Journal of Physiology, 115 (1936), 345–356, with Doris M. Cobb; and “A The oretical Study of the Composition of the Alveolar Air at Altitude,” ibid.. 146 (1946).637–653, with Hermann Rahn and Arthur B. Otis.
A major collection of Fenn’s papers is deposited in the History of Medicine Collection. Edward G. Miner Library. University of Rochester School of Medicine and Dentistry. The collection (about 30 linear feet) includes Fenn’s correspondence, materials relating to his work for scientific societies, and his laboratory notebooks.
II. Secondary Literature. Hermann Rahn provides the fullest sketches of Fenn’s life and work: “Wallace O. Fenn,” in Respiration Physiology, 5 (1968), vii-xii, written with P[ierre] D[ejours]; “Wallace O. Fenn, President of the American Physiological Society, 1946–1948,” in The Physiologist, 19 (1976), 1–10; and his memoir in Biographical Memoirs. National academy of Sciences. 50 (1979), 141–173. These and twenty-three other biographical notices on Fennn, principally from professional journals, are reprinted in Augusta Dustan, ed., In Memoriam. Wallace O. Fenn, 1893–1971 (n.p., ). The American Physiological Society, Bethesda, Md., has a volume of nearly 100 typescript letters, solicited by Clara B. C. Fenn, in which colleagues and students present their recollections of him, Wallace O. Fenn, 1893–1971. Memories and Facts from Friends Here and Abroad (Rochester, N.Y., 1976); and a printed program. A Memorial Service for Wallace Osgood Fenn, 1893–1971 (Rochester, 1971), with attached remarks delivered at the service and a copy of Fenn’s curriculum vitae.
John Harley Warner