World of Scientific Discovery on Edward Calvin Kendall
Edward Kendall is known for two major contributions to biochemical knowledge. The first of these was his isolation of the thyroid hormone thyroxine. In addition, he isolated several steroid hormones produced by the cortex (outer covering) of the adrenal gland, one of which is cortisone, playing a major role in demonstrating its medical use. For his work with cortisone, Kendall shared part of the 1950 Nobel Prize in physiology or medicine with his colleague Philip Hench.
Throughout his career, Kendall often relied on intuition rather than strict laboratory procedure in performing his research. After retiring from the Mayo Clinic in 1951, he continued his research at Princeton University. Kendall was born in South Norwalk, Connecticut, where his father was a dentist. He received both his bachelor's degree (1908) and his doctorate (1910) from Columbia University. The theory of hormones had been developed in the early years of the century by the British physiologists Ernest Starling and William Bayliss (1860-1924), describing glandular secretions that control body functions. In 1910, Kendall began working to isolate a thyroid hormone, first at a pharmaceutical company (Parke Davis and Co.) and then at St. Luke's Hospital in New York. By 1913, he had made a much more pure thyroid gland extract than previously was available, showing its activity in both experimental dogs and human patients.
In 1914, he joined the staff of the Mayo Clinic, in Rochester, Minnesota, where the founders were interested in studying and treating thyroid diseases. By the end of the year, Kendall had isolated the crystalline form of the hormone, later named thyroxine, and shown its activity in successful treatment of patients with underactive thyroid glands. In studying how thyroxine affects oxidation processes in the body, he needed the coenzyme glutathione, a peptide formed from the amino acids cysteine, glutamic acid, and glycine. Since it was not available in pure form, Kendall and his associates independently isolated and synthesized it.
During the 1930s, Kendall turned his attention to the hormones of the adrenal cortex after an adrenal extract had been successfully used to treat Addison's disease, which results from atrophy of the gland. In 1933, he isolated a crystalline substance, which he called "the" hormone, because it was then believed that the cortex secreted only a single hormone. However, further research showed that several substances were present in his crystals, none of them necessarily a hormone. The next year, Kendall and others independently suggested that the adrenal cortex secretes more than one hormone.
Over the next two years, Kendall isolated a series of crystalline substances, to which he gave alphabetical titles. Kendall's Compound E, later named cortisone, was independently isolated by three groups of scientists, but only Kendall converted it to a related compound, a diketone, which had already been demonstrated to be active. Kendall deduced that Compound E is a steroid. During World War II Kendall directed a program to synthesize and produce quantities of Compound E, because some medical authorities thought it might help prevent injury-related stress and surgical shock in wounded military personnel. Hench, who was working on treatment methods for rheumatoid arthritis, and Kendall determined to try using Compound E on arthritic patients. In 1948, after a supply of it was available, they used it as a treatment for the first time. In 1949, they named Compound E cortisone. Kendall's Compounds B and F were later identified by other scientists as the hormones corticosterone and cortisol ( hydrocortisone).
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