Otto Loewi

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Otto Loewi (June 3, 1873 – December 25, 1961) was a German-American pharmacologist. His discovery of acetylcholine helped in enhancing medical therapy and personally earned for him the 1936 Nobel Prize in Physiology or Medicine which he shared with Sir Henry Dale.

1 Research
2 Biography
3 References
4 External links

[edit] Research

In his most famous experiment, Loewi took fluid from one frog heart and applied it to another, slowing the second heart and showing that synaptic signaling used chemical messengers.

Before Loewi's experiments, it was unclear whether signalling across the synapse was bioelectrical or chemical. Loewi's famous experiment, published in 1921, largely answered this question. According to Loewi, the idea for his key experiment came to him in his sleep. He dissected out of frogs two beating hearts: one with the vagus nerve which controls heart rate attached, the other heart on its own. Both hearts were bathed in a saline solution (i.e. Ringer's solution). By electrically stimulating the vagus nerve, Loewi made the first heart beat slower. Then, Loewi took some of the liquid bathing the first heart and applied it to the second heart. The application of the liquid made the second heart also beat slower, proving that some soluble chemical released by the vagus nerve was controlling the heart rate. He called the unknown chemical Vagusstoff. It was later found that this chemical corresponded to acetylcholine (Kandel, et al 2000).

Loewi's investigations “On an augmentation of adrenaline release by cocaine” and “On the connection between digitalis and the action of calcium” were profound concepts and were studied relentlessly by others decades later.

He also clarified two mechanisms of eminent therapeutic importance: the blockade and the augmentation of nerve action by certain drugs.

He is almost as famous for the means by which the idea for his experiment came to him as he is for the experiment itself. On Easter Saturday 1923, he dreamed of an experiment that would prove once and for all that transmission of nerve impulses was chemical, not electrical. He woke up, scribbled the experiment onto a scrap of paper on his night-stand, and went back to sleep.

The next morning he arose very excited because he knew this dream had been very important. But he found, to his horror, that he couldn't read his midnight scribbles.

That day, he said, was the longest day of his life, as he tried, without success,to remember his dream.

That night, he had the same dream. This time, he got up, went to the lab, did the experiment, and by dawn, knew that there was a Nobel in his future. Fourteen years later, there was.

[edit] Biography

Loewi was born in Frankfurt, Germany. He received his medical doctoral degree from University of Strasbourg (then part of Germany) in 1896. He was never particularly interested in clinical work, so after seeing a number of deaths due to incurable diseases such as tuberculosis and pneumonia, he decided to direct his energies to pharmacology research.

Beginning in 1898, he spent many years in Austria, where his first lines of research were in the area of metabolism. Loewi investigated how vital organs respond to chemical and electrical stimulation. He also established their relative dependence on epinephrine for proper function. Consequently, he learnt how nerve impulses are transmitted by chemical messengers. The first chemical neurotransmitter that he identified was acetylcholine.

In 1903, he accepted an appointment at the Karl Franz University in Graz, Austria, where he would remain until being forced out of the country in 1938. He married Guida Goldschmiedt in 1908. They had three sons and a daughter. He was the last Jew hired by the University between 1903 and the end of the war.

After being arrested, along with two of his sons, on the night of the German invasion of Austria, March 11, 1938, Loewi was released on condition that he "voluntarily" relinquish all his possessions to the Nazis. Loewi moved to the United States in 1940, where he became a research professor at the New York University College of Medicine. In 1946, he became a naturalized citizen of the United States. In 1954, he became a Foreign Member of the Royal Society. He died in New York City on December 25, 1961.

The caption under the photo is incorrect. His gold Nobel medal resides at the Royal Society in London, but the diploma is at the Karl Franz University in Graz, Austria, where he was on faculty from 1903 until he was forced out in 1938.

[edit] References

Nobel Lectures, Physiology or Medicine 1922-1941, Elsevier Publishing Company, Amsterdam, 1965.
Kandel ER, Schwartz JH, Jessell TM. Principles of Neural Science, 4th ed. McGraw-Hill, New York (2000). ISBN 0-8385-7701-6