Santiago Ramón y Cajal

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Santiago Ramón y Cajal

Santiago Felipe Ramón y Cajal (born May 1, 1852 in Petilla de Aragón , Navarra , Spain , † October 17, 1934 in Madrid ) was a Spanish medic and histologist . In 1906 he received the Nobel Prize for Physiology or Medicine together with the Italian physician and physiologist Camillo Golgi in recognition of all of their studies and their numerous publications. Santiago Ramón y Cajal mainly worked on the fine structures of the nervous system , especially the brain and the spinal cord .

Life

Ramón y Cajal was the son of a doctor with an interest in anatomy who performed dissections himself. The changing places of work of his father meant that Ramón y Cajal spent his early childhood in several towns and cities in Aragon , in Larrés (1853), Luna (1855), Valpalmas (1856) and Ayerbe (1860). After primary school in Jaca , he completed high school and high school in Huesca . At the age of fourteen he also received training as a barber. After his family moved to Saragossa in 1870, he embarked on a medical career, where he also assisted his father with sections at the medical school . In June 1873 he finished his studies and began his career in the army, where he was appointed as a doctor in the medical service. In 1874/1875 he took part in an expedition to Cuba during the first Cuban War of Independence , where he became infected with malaria and tuberculosis . After his return to Spain in 1875, the young doctor accepted a position as an assistant doctor at the Medical Faculty of the University of Zaragoza . In 1877 he received his doctorate from the Complutense University of Madrid . In 1879 he became director of a museum in Saragossa. In 1883, Santiago Ramón y Cajal became professor of descriptive and general anatomy at the University of Valencia , where he worked on his later work Manual de Histología normal y técnica micrográfica . In 1887 he moved to the University of Barcelona as Professor of Histology and Pathology and in 1892, in the same fields, to the Complutense University of Madrid. In 1900 he became director of the Instituto Nacional de Higiene and the Investigaciones Biológicas .

In 1906 Santiago Ramón y Cajal received the Nobel Prize for Physiology or Medicine, together with Camillo Golgi “in recognition of their work on the structure of the nervous system.” In the same year he was elected a corresponding member of the Academy of Sciences in Göttingen , and since 1909 he has been foreign Member of the Royal Society . In 1916 he was elected to the Académie des Sciences in Paris and in 1920 to the National Academy of Sciences . In 1913 he was elected an Honorary Fellow of the Royal Society of Edinburgh .

His outstanding works were Textura del sistema nervioso del hombre y de los vertebrados (1899–1904) and Estudios sobre la degeneración y regeneración del sistema nervioso (1913/1914). The doctor died in Madrid on October 17, 1934. He was a member of a Spanish Masonic Lodge in Saragossa. Together with Pío del Río Hortega , Tello, Nicolás Achúcarro and Rafael Lorente de Nó, he is considered the founder of the Spanish neurohistological school.

Santiago Ramón y Cajal was married to Silveria Fañanás García since 1879, the couple had four daughters and three sons.

Services

Ramón y Cajal's most important work was the study of the fine structure of the central nervous system. Cajal used a histological staining technique that had recently been developed by Camillo Golgi. Golgi found that when brain tissue was treated with a silver nitrate solution, a relatively small number of neurons in the brain were colored dark. This allowed Golgi to clarify the structure of individual neurons in detail and led him to the conclusion that nerve tissue forms a cohesive network (or network) of interconnected cells - very similar to what was known from the circulatory system.

With Golgi's method, however, Ramón y Cajal came to very different conclusions. In 1887 he postulated that the nervous system consists of billions of individual neurons and that these cells are polarized . Instead of a coherent network, Cajal suggested that neurons communicate with one another via special connections - the synapses . The term "Synapse" was coined in 1897 by Charles Scott Sherrington . This hypothesis became the basis of neuron theory , which states that the smallest unit of the nervous system is the single neuron. It was later found by electron microscopy that each neuron is completely surrounded by a cell membrane . This discovery strengthened Cajal's theory over Golgi's hypothesis.

With the discovery of electrical synapses ( gap junctions : direct connections between cells, here nerve cells), however, it became clear that Golgi's hypothesis was at least partially correct.

Ramón y Cajal postulated that the direction and speed of growth of the nerve processes ( axons ) are controlled by a growth cone at their ends. He had discovered that neuronal cells could receive chemical signals that indicated a direction for growth ( chemotaxis ).

Ramón y Cajal carried out intensive studies to prove qualitative differences between the brains of humans and animals. To this end, he put forward the hypothesis: "The functional superiority of the human brain is very closely related to the astonishing abundance and the unusual variety of shapes of the so-called neurons with short axons." That was the core of the problem of the cerebral cortex , and finally he had to admit: " ... the indescribable complexity of the structure of gray matter is so intricate that it defies the persistent curiosity of researchers and will defy for many centuries to come. "

In 1903, Ramón y Cajal discovered the Cajal bodies named after him in 1999 in cell nuclei he had examined .

Conflict with Camillo Golgi

The different results that Golgi's staining method led to in Golgi and Cajal created an enmity between the two. Cajal developed the method further, stained nerve cells, mainly from chickens and small mammals, and published around 45 papers on the nervous system between 1888 and 1891. But where Golgi was of the opinion that the neurons are continuously connected, Cajal argued that the brain is made up of autonomous cells. When they were awarded a joint Nobel Prize, they were anything but happy about it. At least that is evident from their acceptance speeches; both men teased the other's "deliberate disregard" and "repulsive mistakes".

Drawings by Santiago Ramón y Cajal

  • Drawing of the neural connections of the rodent hippocampus . Histologie du Systeme Nerveux de l'Homme et des Vertebretes, Vols. 1 and 2. A. Maloine. Paris. 1911.

  • Drawing of the cells of the chicken cerebellum . Estructura de los centros nerviosos de las aves, Madrid, 1905.

  • Drawing of the tectum opticum of the sparrow . Estructura de los centros nerviosos de las aves, Madrid, 1905.

  • Drawing of Purkinje cells (A) and granule cells (B) of the cerebellum of the pigeon by Santiago Ramón y Cajal, 1899. Instituto Santiago Ramón y Cajal, Madrid, Spain.

Honors

Publications

  • Estudios sobre la degeneración de sistema nervioso. 2 volumes, Madrid 1913–1914.
  • Vacation Stories. Five Science Fiction Tales. Translated by Laura Otis . University of Illinois Press, 2001.
  • Advice for a Young Investigator. Translated by N. Swanson and LW Swanson. Bradford Book, MIT 1999.

swell

  1. ^ Instituto Nacional de Sanidad (España): D. Santiago Ramón y Cajal: (crónica de la velada necrológica). October 26, 1934, Retrieved September 5, 2019 .
  2. ^ Entry on Ramon y Cajal, Santiago (1852 - 1934) in the Archives of the Royal Society , London
  3. ^ Fellows Directory. Biographical Index: Former RSE Fellows 1783–2002. Royal Society of Edinburgh, accessed October 15, 2019 .
  4. ^ Ingrid Kästner: Santiago Ramón y Cajal. In: Wolfgang U. Eckart , Christoph Gradmann (Hrsg.): Ärztelexikon. From antiquity to the 20th century. 1st edition. CH Beck, Munich 1995, p. 296; Medical glossary. From antiquity to the present. 2nd Edition. 2001, p. 259; 3. Edition. Springer Verlag, Heidelberg / Berlin / New York 2006, p. 270. Ärztelexikon 2006 , doi: 10.1007 / 978-3-540-29585-3 .
  5. ↑ Walle JH Nauta , Michael Feirtag: Neuroanatomie. Heidelberg 1990.
  6. ^ Juan A. De Carlos, José Borrel: A Historical Reflection of the Contributions of Cajal and Golgi to the Foundation of Neuroscience .
  7. ↑ 2017 | United Nations Educational, Scientific and Cultural Organization. Accessed March 14, 2018 (English).

Web links

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personal data
SURNAME Ramón y Cajal, Santiago
ALTERNATIVE NAMES Ramón y Cajal, Santiago Felipe (full name)
BRIEF DESCRIPTION Spanish medic and Nobel Prize laureate in medicine 1906
DATE OF BIRTH May 1, 1852
PLACE OF BIRTH Petilla de Aragón , Navarre
DATE OF DEATH October 17, 1934
Place of death Madrid