Carl Ludwig

Karl Friedrich Wilhelm Ludwig was born on December 29, 1816 in Gottingen, Germany. His father had been on officer in the Napoleonic Wars. Ludwig graduated high school in 1834 and started his medical studies at the University of Marburg. He was relegated from the university because of his political activities and he continued his medical studies at the University of Erlangen and at the School of Surgery at Bamberg. He returned to Marburg in 1839 and finished his medical doctorate in 1840. After graduation he worked in the laboratory of Robert Bunsen and as a prosector in the school of anatomy at the University of Marburg. In 1846 he was appointed professor extrordinary in anatomy at Marburg and in 1849 he was appointed professor of anatomy at the University of Zurich. Six years later he went to Vienna and and an appointment teaching at the Josephinium, a school for military surgeons. In 1865 he took a position at the newly created department of physiology at the University of Leipzig. In 1869 he was called to develop and be the director of the newly created physiological institute at Leipzig that would eventually be named after him. He remained there until his death.

Ludwig's research dealt with the circulation of fluids in the body. His first paper, published in 1842, described the circulation of blood in the kidney and was the first to describe the function of the glomerulus. He also investigated blood pressure and designed an instrument to measure and record it. His investigations also included secretory glands and lymph circulation. More important than any of his research results it was his methods that had a lasting impact on the study of physiology. Up until the time of Ludwig physiological research involved the belief in vital forces, forces generated by the body that sometimes went against physical law. Ludwig's insight was that the forces of physics and chemistry played a important role in physiological processes and his methods sought to show how these natural processes affected physiological systems. For his insights and use of methods he is often called the father of modern physiology.

Honors won by Ludwig include the Copley Medal in 1884, given by the Royal Society of London and foreign membership in the Royal Swedish Academy of Science in 1869.

Ludwig died on April 23, 1895.


References:

Zimmer, Heinz-Gerd; "Carl Ludwig"; retrieved from feps.org

"Carl Ludwig" in the 1911 Encyclopedia Britannica

Carl Ludwig Wikipedia Entry

Walter Hess

Walter Rudolf Hess was born on March 17, 1881 in Frauenfeld in the Swiss canton of Thurgau. He was the second of three children on Clemens and Gertrude Hess. His father was a physics teacher in a grammar school and ran a weather station. Hess learned physics from his father and helped the family electrify the family's apartment. He began studying medicine in Lausanne in 1899, finishing his studies in Berlin, Kiel, and Zurich. After passing his qualifying medical exam in Zurich, in 1906, he served as a surgeon's assistant. While a surgeon's assistant he developed a device to measure blood viscosity that was widely used clinically but has been replaced by the measurement of blood sedimentation rate. He was later an ophthalmologists's assistant and then an ophthalmologist. Hess's interest was in physiology and in 1912 he gave up a prosperous practice to take the position of a physiologist's assistant, working under Justus Gaule. In 1916, with Gaule's retirement, Hess first became interim director and then director and professor of the Department of Physiological Institute at the University of Zurich. He remained there until his retirement in 1951.

Hess's physiological studies included the circulatory system, but he is most remembered for his research into brain function. Using a fine tipped electrode he was able to stimulate regions of the mid-brain and develop a map of its functions. Mammalian brains are largely divided three regions: the hindbrain, the midbrain, and the forebrain, moving up from the spinal cord to the head (for a diagram of the brain showing some of the functions of different regions see here). Different regions of the brain have different functions with the hind brain, or brain stem, having body maintenance functions including body temperature, heart and breathing control. The forebrain includes the four lobes of the cerebellum which control thought, memory, and movement. Hess, using his electrode to stimulate regions of the hypothalamus, a region of the mid brain, found that he could stimulate excitement or apathy. He also found regions where he could stimulate hunger and thirst. For his researches he was awarded the 1949 Nobel Prize in medicine and physiology "for his discovery of the functional organization of the interbrain as a coordinator of the activities of the internal organs."

Other honors won by Hess include the Marcel Benoist Prize in 1932 and honorary doctorates from the Universities of Bern, Geneva, and Freiburg and from McGill University.

He died on August 12, 1973.


References:

Hess, C.W.; "Walter Hess (17.3.1881-12.6.1973)"; Schwiezer Archiv fur Neurologie und Psychiatrie (2008)159:259-261

Walter Hess Nobel Biography

Walter Hess Wikipedia Entry

Sir Thomas Lauder Brunton

Sir Thomas Lauder Brunton was born on March 14, 1844 in Bowden, Roxburghshire (in Scotland, near the English border) to James Brunton and his wife Agnes. There are conflicting accounts of his early education, some saying he studied privately and others that he studied at the parish school and then a school at Melrose. He went to Edinburgh University where at his father's urging he began to study law. Taking classes in chemistry and physics in his spare time he soon became so interested in them that he changed his focus. He qualified in 1866, taking the M.B, C.M.Edin. degree with honors and M.D. in 1868 with honors for his thesis on "Digitalis, with some observations on the urine". For a year (1866-67) he served as house physician at the Royal Infirmary, Edinburgh.

After his education he went abroad, intending to visit places mentioned in the story of Joseph from the Bible, visiting Egypt and Syria. He continued his travels visiting Turkey, Greece and Italy. he went to Vienna, where he did laboratory work on digitalis (he never published his results), Berlin, where he analyzed the nuclei of blood cells, Amsterdam and Leipzig where he was one of the first students to be admitted to Carl Ludwig's new institution. It was there that he worked studying arterioles and capillaries making experiments on the effects of amyl nitrate and sodium nitrate. It is the use of amyl nitrate for the relief of angina pectoris that he is chiefly remembered for (drawing on the work of Arthur Gamgee and Benjamin Ward Richardson). Inhaled amyl nitrate causes vasodilation in the coronary arteries and reduced systemic resistance to blood flow.