Erlanger (Erlanger), Joseph

January 5, 1874, Mr.. - December 5, 1965
The American physiologist Joseph Erlanger was born in San Francisco (California), where he lived, his father Herman Erlanger after emigration from Wц?rttemberg (Germany) in 1842, Mr.. When in 1849. started 'gold rush', Erlanger Sr. sailed on a ship from New Orleans to Panama, crossed the Isthmus of Panama on mules and the sea got to California. For a while he worked at a gold mine, and then started their own business and married the sister of his partner Sarah Galinger. No one in the family had no education beyond primary school, and only Joseph - the sixth of seven children - was able to go to college. From childhood he was interested in animals and plants and decided to get a medical education. After graduating from high school for boys in San Francisco in 1891. he entered the University of California at Berkeley.
In 1895, Mr.. E. graduated from university and entered the third year at the newly opened medical school at Johns Hopkins in Baltimore (Maryland). This was the first American institution, the main focus of which was placed not only on traditional training, but rather on research papers. Work on embryology, that E. performed on the senior year, opened his ability to research activities. Studying at medical school, E. continued research on the neurobiology and digestion. In 1899. He received a medical degree and worked as an intern during the year under the leadership of William Osler, Canadian physician and lead clinician at the time, who held the post of professor of medicine at Johns Hopkins School. In 1900, Mr.. E. joined the department of physiology of the school.
Since the first E. was the youngest member of the department, he was instructed to prepare visual aids for lectures on the physiology. Once he broke a valuable instrument - sphygmograph; with this glass instrument recorded pulsation of the arteries thumb and index fingers of both hands. To lecture was not disrupted, E. developed a new sphygmograph which can measure blood pressure in the shoulder. Later, this device has been patented and received in the market for sale, although subsequently there were more complex instruments, whose work was based on the same principle.
In the Johns Hopkins School E. continued research on the regulation of blood pressure and conduct impulses from the atria to the ventricles of the heart. With the invention of a special time for the regulation of pressure he was able to analyze atrial and ventricular blockade of all degrees.
In 1906, Mr.. E. asked to become chair of a new medical school at the University of Wisconsin-Madison. The first two years of work in this position E. organization dedicated to the department, and then returned to the experiments for the excitation from one chamber of the heart to other. Four years later, E. moved to St. Louis, where he became head of the Department of Physiology, Medical School, University of Washington. The next four years he was completely devoted to administrative work of the department where he was to work for 35 years. In 1915, Mr.. He returned to the study of blood pressure, focusing on the mechanisms of formation of Korotkoff noises, listening to the measurement of blood pressure and caused the sudden dilation of the arteries. During the First World War Z. studied the effect of blood loss and shock on the wound state of the cardiovascular system. The staff, which E. invited to the chair of physiology at the University of Washington, was Herbert C. Gasser. At a time when E. worked at the University of Wisconsin, Gasser was a student and then became a professor of pharmacology. With E. They began to study the electrical activity of nerves.
In studies of the Italian physician and physiologist in the XVIII. Luigi Galvani found that the pulses transmitted along the nerves are the electrical nature. However, further study of these pulses, or the so-called action potentials, was hampered by the fact that they were short-lived. Subsequently, E. wrote that 'they were so brief that in 1921. there was no hope that someday it will be possible to study in detail their shape '. Then for the study of electrical processes of nerve tissue were mostly used string galvanometer (devices, . measuring currents on the electromagnetic fields created by them), . however, these devices were not sufficiently sensitive to record action potentials - pulses with the amplitude, . only a few microvolts,
. In addition, the string galvanometer often broke.
Gasser and his colleague Sydney Nyukomer overcome some of these difficulties, with a tube connecting the galvanometer amplifier (similar to that used by Guglielmo Marks in radio). With these amplifiers scientists were able to increase the amplitude of the action potential to such a degree that allows us to study this potential. At the same time, the system of the amplifier with a galvanometer remained inertial. Since the duration of action potentials was less than a millisecond, to study their various components required device, enabling us to continuously record a very rapid change.
In 1920, Mr.. Gasser learned that 'Uestern Electric Company' has just developed a sensitive electron-beam oscilloscope. After unsuccessful attempts to contact the company asking for cathode-ray tube E. Gasser and developed their own tube of the flask for distillation of water. Combining it with the amps, they were able to record the first time the dynamics of action potentials in nerves. Many works were carried out only after 1932, when the researchers were able to achieve a sufficiently large gain.
Nerve trunks are composed of nerve fibers (processes of individual nerve cells) with different properties. The most important difference between these fibers - their diameter. The most important discovery that E. and Gasser done with the help of an oscilloscope, consisted in the confirmation of the hypothesis that the thick fibers carry nerve impulses faster than the thin, this hypothesis was made in 1906. Swedish physiologist Gustaf Gotlinom, but check it before it was impossible. With the help of instruments developed by the E. and Gasser were able to study in detail the shape of the action potential, which played an important role in establishing the theory of nerve excitation Alan Hodgkin and Andrew Huxley.
In 1944, Mr.. E. and Gasser were awarded the Nobel Prize in Physiology or Medicine "for discoveries concerning the number of functional differences between the different nerve fibers'. During the Second World War, the award ceremony was canceled, but the greeting speech broadcast on radio. It researcher at the Karolinska Institute Ragnar Granit summarized the work of E. and Gasser. He said that 'one of the major achievements of the scientists was the discovery of the fact that the sensory nerves are very different from the motor'. E. read the Nobel lecture in Stockholm in 1947
E. electrophysiologist and Alexander Forbes were leaders of the informal group 'Aksonologi' - an association of neurologists from various laboratories and institutes, . worked in the late 20's - early 30-ies., . share information and results of laboratory,
. As a researcher and lecturer E. had a great influence on the development of neurophysiology in the United States of America. In 1946
he retired, received the title of honorary professor of physiology at the University of Washington, and continued to conduct research and publish articles.
In 1906, Mr.. E. married a San Francisco resident Amy Hirstel. In the family they had two daughters and a son. E. was a wonderful family man, loved to engage in photography and mountain climbing, playing the flute. December 5, 1965, Mr.. He died in St. Louis.
E. was a member of the National Academy of Sciences of the USA, . American Philosophical Society, . American Physiological Society, . American Medical Association, . American Association for the Advancement of Science, . American Association of Physicians and the Society for Experimental Biology and Medicine,
. He had honorary degrees from California, Wisconsin, Pennsylvania, Michigan and Washington University, and Johns Hopkins University and the Free University of Brussels.