Ebashi Setsuro

Ebashi Setsurō ( Japanese 江橋 節 郎 ; born August 31, 1922 in Tokyo ; † July 17, 2006 in Okazaki ) was a Japanese physiologist and pioneer in the field of research into signal transmission in living cells . He succeeded in the early 1950s a. a. evidence that calcium ions play an important role in muscle fibers to contract - a finding that is mentioned in every textbook of physiology for decades.

Life

Even as a child, Ebashi stood out for his special talent, as he skipped a class in both elementary school and middle school. He was later admitted to Dai-ichi High School , the most prestigious high school in Japan at the time. After graduating, he was appointed Professor of Pharmacology at the University of Tokyo at the age of 36 .

One of his outstanding achievements is that he largely single-handedly demonstrated how action potentials that reach the surface of muscle fibers can shorten protein threads.

As early as the 1940s, Albert Szent-Györgyi had largely clarified the biochemical basis of muscle contraction. Jean Hanson and Hugh Huxley then described the structure and importance of the proteins actin and myosin that are active in muscles . However, it remained unclear how the nerves manage to trigger the contraction of the muscle fibers.

Ebashi discovered that in the absence of calcium ions there is no contraction, even if there is plenty of ATP . Conversely, a violent contraction can be caused if only traces of calcium - one micromolar - are added. Other researchers before him had overlooked the calcium dependency, since their experiments were apparently always slightly contaminated by traces of calcium from laboratory glassware and chemical reagents .

Despite its clear findings, Ebashi's studies did not receive much attention until the early 1960s. For years, most of my colleagues were of the opinion that a 'simple' ion could by no means be decisive in controlling muscle contraction; rather, they suspected that this role was assigned to an as yet undiscovered, complex organic molecule.

Ebashi suffered a stroke back in 2000. An obituary in the journal Nature said that Ebashi was "one of the world's most respected scientists in the fields of physiology and pharmacy".

He received the Asahi Prize in 1968 and he was a. a. Awarded the Order of Culture in 1975 , the highest Japanese honor for researchers. In 1979 he received the Croonian Lecture of the Royal Society and in 1999 was awarded the International Prize for Biology . In 1971 he was elected a member of the Leopoldina Scholars' Academy , in 1975 in the American Academy of Arts and Sciences , in 1996 in the National Academy of Sciences .

literature

• Makoto Endo: Setsuro Ebashi (1922-2006). In: Nature . Volume 442, 2006, p. 996, doi: 10.1038 / 442996a

Japanese name: As is common in Japan, the family name comes before the first name in this article . Thus Ebashi is the family name, Setsurō the first name.