Earl Howard Wood

53rd APS President (1980-1981)
Earl Howard Wood
(1912 - 2009)


On Wednesday, 31 July 1985, the New York Times, in a major editorial on the use of animals in biological research and testing, commended APS by name for its policy supporting humane care and use of laboratory animals. This policy is not something new for the Society. The result of deliberations extending over many years and involving many of the Society's members, committees, and officers, it expressed a long-standing concern. For example, four years earlier (1981) Ernst Knobil, as a recent past president, and Earl H. Wood, as past president of APS and president of FASEB, offered testimony before the U.S. House of Representatives Subcommittee on Science, Research, and Technology regarding the necessity 1) of continuing utilization of animals for biomedical research and 2) of avoiding any suspicion of abuse or neglect. Wood mentioned this problem in his past president's address (10) by noting, "The very active promotion of legislative proposals by these types of well-organized and financed animal rights groups is a most serious threat to continued progress in the biomedical sciences." More recently he added. "The ongoing, progressively increasing antivivisection activities seriously threaten continued progress in the biomedical sciences." In 1983 the Society selected Wood to serve as chairman of a blue ribbon panel that reviewed the case of Edward Taub, a Silver Spring, Maryland, researcher whose laboratory was raided by animal rights zealots; 117 charges of animal cruelty were filed against him.

Born in Mankato, Minnesota, after graduation from Macalester College in St. Paul in 1934 Wood entered the School of Medicine of the University of Minnesota but gave up his medical studies temporarily for training in Maurice Visscher's department, where he received the M.S. degree in 1939. Two years later (1941) he was awarded both the M.D. and the Ph.D. degrees, the latter for research on water and electrolytes of cardiac muscle, especially under the influence of digitalis (1). In fact, the year 1940-41 was spent at the University of Pennsylvania as an NRC fellow in the Department of Pharmacology, and for the following year he was instructor in pharmacology at Harvard. In 1942 he returned to Minnesota, to the Aeromedical Unit of the Mayo Foundation Laboratories, where he progressed steadily in rank in the Mayo Graduate School and then in the Mayo Medical School to become professor of physiology and of medicine in 1951. He officially retired from these positions in 1982.

Wood has written of his training, "My most important preceptors in science were Prof. M. B. Visscher (Minnesota), Prof. A. N. Richards (Pennsylvania), and Prof. Otto Krayer (Harvard). I had the greatest respect for Otto Krayer; he was a really exceptional gentleman and scholar."

Wood's research interests fall into three main classifications. He began, as noted above, by studying the action of cardiac glycosides in heart-lung preparations, and with Gordon Moe he demonstrated that the positive inotropic effects of digitalis glycosides are associated with loss of intracellular myocardial potassium (1). This loss may be accompanied by an increase in intracellular calcium, which in turn causes an increase in efficiency of excitation-contraction coupling and the positive inotropic effect. Twenty-seven years later (7) Wood and his associates showed that dramatic positive or negative inotropic effects can be produced at constant cardiac fiber length by relatively small induced changes in the plateau phase of the action potential. Again these effects were postulated to be caused by changes in intracellular calcium concentration and in efficiency of excitation-contraction coupling. This report was the first to describe use of the sucrose gap method of potential clamping for cardiac muscle fibers. Another fundamental study of cardiac physiology showed that there are position-dependent regional differences in pericardial pressures that influence cardiac function (8).

The second theme of Wood's research is protection against positive gravitational effects during high-speed aerial combat and dive-bombing maneuvers. An active program of investigation carried out with the Mayo human centrifuge and summarized relatively soon after the war (2) included the discovery that protection against blackout requires procedures or devices that maintain blood flow to the head by actually producing hypertension at heart level. This led to the development of a simplified single-pressure suit and its associated G-activated and G-compensated pneumatic valve. In 1963 the later work of the group was described (6), with a theoretical model of changes in regional lung volume, ventilation perfusion, and pleural pressures caused by changes in the direction and/or magnitude of gravitational-inertial forces. The papers these reviews were based on made the Mayo laboratory a world leader in study of gravitational stress.

Thirdly, Wood and his associates have made notable contributions to laboratory methods and techniques, including 1) a Statham unbounded strain gauge for measuring blood pressure; 2) an oximeter for on-line, real-time measurement of oxygen saturation while blood is being withdrawn for diagnostic purposes; and 3) an absolute-reading ear oximeter; all three are generally used throughout the world. Their development and their properties have revolutionized procedures for diagnostic cardiac catherization, as summarized by Wood in 1950 (7), and eventually they led to on-line, real-time monitoring during cardiac surgery (5). Studies of dye-dilution techniques began with continuous recording of Evans blue dye concentrations, then of indocyanine green, and finally led to an article summarizing these methods and their use (4). The most recent interest of Wood and his colleagues is a high-speed, computer-based X-ray scanning system that gives accurate and three-dimensional views of moment-to-moment changes in, for example, heart, lungs, or circulation of intact animals or humans. Known as the "dynamic spatial reconstructor," the machine is a high-speed, synchronous, volumetric whole-body computer-assisted tomographic (CT) scanner. It was described in 1977 (9) and in some detail in Wood's past president's address that speaks to the multiple grant requests and many site visits required to secure funding for construction of the machine (10).

For his development of the anti-G suit, Wood was awarded the Presidential Certificate of Merit by Harry Truman in 1947. He has received from Macalester College an honorary degree of D.Sc. in 1950 and a Distinguished Citizen Award in 1974. In 1963 he was given awards by the Aerospace Medicine Association and by Modern Medicine. The American College of Chest Physicians (1974), the Mayo Foundation (1978 and 1984), and the Biomedical Engineering Society (1978) have all honored him with lectureships. He is an honorary member of the Royal Netherlands Academy of Arts and Sciences (1977) and of the American College of Cardiology (1978). In 1982, he received an honorary degree, doctor of medicine, from the University of Bern, Switzerland, and in the following year he was given both the Humboldt Prize for Senior U.S. Scientists by the government of West Germany and the John Phillips Memorial Award of the American College of Physicians. Wood has been a visiting professor at the University of Bern (1965-66), an honorary research fellow in the Department of Physiology at University College, London (1972-73), and a visiting professor at the University of Kiel, West Germany (1983).

When he spoke to the society as past president, Wood recalled that the first such address was given by Wallace Fenn at the University of Minnesota in 1948, and Wood added that he had heard all but two of the ensuing thirty-three addresses. Few members of APS can claim more. Wood became a member in 1943. He was active at first mainly in the Circulation Group and served as a member of its Steering Committee (1962-1964; chairman, 1963-1964). He received its Carl J. Wiggers Award in 1968. He was elected to APS Council in 1977 and became president elect in 1979. From 1978-1980 he was chairman of the Centennial Celebration Committee, and from 1982 to 1985 he served on the Finance Committee. Responsibilities with FASEB ran very much in parallel with those in the Society; in addition to his year as president of FASEB (1981-1982), he was a member of the Long-Range Planning and Development Fund Committees (1982-1985) and the Public Affairs Committee (1984-1985).

While he was participating in APS, Wood was likewise active in AHA. From 1962 to 1977 he was a Career Investigator of AHA. He was a member of its Basic Science Council and its Council on the Circulation from 1963, and for three years (1967-70) he was on both the AHA Research Fellowship Review Panel and the Physiology and Pharmacology Research Study Committee. In 1973 he was given the association's Research Achievement Award. A member of the Biomedical Engineering Society from 1970, he was elected president for 1983-1984. He is a fellow of the Aerospace Medical Association (1964-) and its Space Medicine Branch (1976-). For his pioneer research on problems encountered in flight, he has been a consultant and served on committees for many federal agencies and ad hoc groups, beginning with the U.S. Air Force Aeromedical Center in Heidelberg, Germany, in 1946. The list includes also the Bioastronautics Panel of the President's Science Advisory Committee (1962-66); the Advisory Panel on Medical Biological Sciences (1962-67); a working group on Gaseous Environment for Manned Space Craft of NAS (1963-64); the Office of the Director of Defense Research and Engineering (1964-65); NASA panels and study groups (1964-65, 1967-80, and 1978-81); the U.S. Air Force Manned Orbital Laboratory Medical Advisory Group (1969-74); the American Institute of Biological Sciences Medical Program Advisory Council (1963-); and an AIBS ad hoc panel on medical selection and maintenance of crew health, created for NASA with Wood as chairman (1978-81). For a year he was a consultant for the Aerospace Corporation (1964-65), and for six years he served on the NASA Man in Space Committee (1964-70). He has served NIH on the Physiology Fellowship Review Panel (1963-65), the Research Career Development Award Committee (1963-65), the Artificial Heart/Myocardial Infarction Program Advisory Committee (1967-70), the Biomedical Engineering Special Study Section (1970), and the Computer and Biomathematical Sciences Study Section (1974-77).

In addition to membership in the usual, more generalized scientific societies (e.g., AAAS) Wood is a member of the American Society for Clinical Investigation and the Central Society for Clinical Research. He belongs to the Cardiac Muscle Society, the Minnesota Heart Association, and the Minnesota Academy of Sciences. In 1979 he went to China as a member of a delegation representing the American College of Physicians.

Wood grew up in a family with a sister and four brothers, all of whom became distinguished in their several fields. Louise, an executive of the American Red Cross during World War II, eventually became director of all overseas activities of that organization and then served for eleven years as executive director for the Girl Scouts of America. Their brother, Harland, was professor of biochemistry at Case Western Reserve University. Chester (Ph.D., Stanford University), who taught in various schools in Minnesota, was a member of the staff of the University of Minnesota in Duluth and then of the Anchorage Methodist University. Delbert graduated from the St. Paul College of Law, was a member of the staff of the Federal Bureau of Investigation for six years, and then for twenty years was chief special agent for the Illinois Central Railroad. Wilbur received his medical education at Minnesota and after the war established a medical clinic in Littleton, Colorado. From 1942 the family and a few friends have come together each year in the Minnesota woods, since 1944 in their own camp, for a reunion that includes a fall deer hunt and other family traditions. Earl is said to be the one in charge; he sends out rules of the camp, four pages long. He also keeps statistics of each year's hunt and issues a "productivity" report after each season.

When he retired from his position at the Mayo, and from office in the APS, Wood with his sons, Andy and Mark, his close friend Homer Warner (of the University of Utah), Warner's son, Steve, and a friend, Ray Skrocke, sailed from Hawaii to Seattle. Wood wrote of the rough parts of the trip, "winds about 30-40 miles per hour from the north. Seas very rough. Tremendous swells and breakers---at least 20 feet high. . . .Boat often heeling over to 40-45 degrees. Terrifying. . . ."

This voyage must have been a grand way to "wind down" from three years of presidential service to APS.

Selected Publications

1. Wood, E. H., and G. K. Moe. Blood electrolyte changes in the heart-lung preparation with special reference to the effects of cardiac glycosides. Am. J. Physiol. 137: 6-21, 1942.

2. Wood, E. H., E. H. Lambert, E. J. Baldes, and C. F. Code. Effects of acceleration in relation to aviation. Federation Proc. 3: 327-344, 1946.

3. Wood, E. H. Special instrumentation problems encountered in physiological research concerning the heart and circulation in man. Science Wash. DC 112: 705-715, 1950.

4. Wood, E. H., H. L. C. Swan, and H. W. Marshall. Technic and diagnostic applications of dilution curves recorded simultaneously from the right side of the heart and from the arterial circulation. Proc. Staff Meet. Mayo Clin. 33: 536-553, 1958.

5. Wood, E. H., W. F. Sutterer, and D. E. Donald. The monitoring and recording of physiologic variables during closure of ventricular septal defects using extracorporeal circulation. Adv. Cardiol. 2: 61-74, 1959.

6. Wood, E. H., A. C. Nolan, D. E. Donald, and L. Cronin. Influence of acceleration on pulmonary physiology. Federation Proc. 22: 1024-1034, 1963.

7. Wood, E. H., R. L. Heppner, and S. Weidmann. Inotropic effects of electric currents. I. Positive and negative effects of constant electric currents or current pulses applied during cardiac action potentials. II. Hypothesis: calcium movements, excitation-contraction coupling and inotropic effects. Circ. Res. 24: 409-445, 1969.

8. Avasthey, P., C. M. Coulam, and E. H. Wood. Position-dependent regional differences in pericardial pressures. J. Appl. Physiol. 28: 622-629, 1970.

9. Wood, E. H. New vistas for the study of structural and functional dynamics of the heart, lungs, and circulation by non-invasive numerical tomographic vivisection. Circulation 56: 506-520, 1977.

10. Wood, E. H. Past-president's address. Four decades of physiology, musing, and what now. Physiologist 25: 19-32, 1982.