- Heinrich Wilhelm Gottfried von Waldeyer-Hartz
Heinrich Wilhelm Gottfried von Waldeyer-Hartz (
October 6 ,1836 ,Hehlen an der Weser ,Braunschweig ,Germany –January 23 ,1921 ,Berlin ) was a Germananatomist , famous for consolidating the neuron theory of organization of thenervous system and for naming thechromosome . He is also known through two anatomical structures of the human body which bear his name:Waldeyer's gland andWaldeyer's tonsillar ring (thelymphoid tissue ring of thenasopharynx ).The neuron theory
Waldeyer is honoured in the
neuroscience s as the founder, in 1891, of the so-called "neuron theory" and for coining the term "neuron " to describe the basic structural unit of the nervous system. To consolidate and postulate his theory, Waldeyer used the path-breaking discoveries by neuroanatomists (and laterNobel Prize winners)Camillo Golgi (1843-1926) andSantiago Ramón y Cajal (1852-1934), who had used thesilver nitrate method of staining nerve tissue (Golgi's method ). This method allowed them to study in exquisite detail the branching processes of nerve cells (axon s anddendrite s) and how they seemed to interconnect among themselves, forming chains andneural network s which could explain the physiological mechanisms underlying the phenomena of information transfer between neurons. Waldeyer learned Spanish in order to absorb Cajal's extraordinary detailed studies using Golgi's method and became his friend, mentor and promoter in the German-dominated field of microscopic anatomy. The theory was published in a series of papers in the main medical journal of Germany, "Deutsche Medizinische Wochenschrift ", which became extremely influential. However, as Cajal points out, though Waldeyer "supported the theory with the prestige of his authority, he did not contribute a single personal observation. He limited himself to a short brilliant exposition of the objective proofs, adduced by His, Kolliker, Retzius, van Gehuchten and myself, and he invented the fortunate term "neuron". " [Cajal, S. Ramón y. (1954) "Neuron theory or reticular theory: Objective evidence of the anatomical unity of nerve cells." Transl. MU Purkiss and CA Fox. Madrid:Consejo superior de investigaciones científicas.] Cajal's continuing hard work on the following decade was able to prove many aspects of the neuron theory, including the directionality of synaptic transmission, and ultimately Cajal won over Golgi on their dispute on the contiguity vs. continuity of neuron cell contacts.Cytology and embryology
Waldeyer also studied the
basophilic stained filaments which had been found to be the main constituents ofchromatin , the material inside thecell nucleus , by his colleague ofKiel ,Walther Flemming (1843-1905). Although its significance for genetics and for cell biology was still to be discovered, these filaments were known to be involved in the phenomenon ofcell division discovered by Flemming, namedmitosis . as well as inmeiosis . He coined in 1888 the term “chromosome” (1888) to describe them.Among his myriad other anatomical and embryological studies, von Waldeyer became known for his pioneering research on the development of
teeth andhair , many of the terms he invented still in use today. He also published the first embryological, anatomical and functional studies about the naso-oro-pharyngeal lymphatic tissue, which received his name.Bibliography
* Über Karyokinese und ihre Beziehungen zu den Befruchtungsvorgängen. "Archiv für mikroskopische Anatomie und Entwicklungsmechanik", 1888, 32: 1-122. Paper about mitosis and chromosomes.
* Ueber einige neuere Forschungen im Gebiete der Anatomie des Centralnervensystems. "Deutsche medicinische Wochenschrift", Berlin, 1891: 17: 1213-1218, 1244-1246, 1287-1289, 1331-1332, 1350-1356. (About some new researches in the field of anatomy of the central nervous system). His most famous statement and summary of the neuron theory.
* W. von Waldeyer-Hartz: "Lebenserinnerungen". Bonn, 1920; 2nd edition; Bonn, 1921; 3rd edition, 1922. His memoirs.References
External links
* [http://www.whonamedit.com/doctor.cfm/1846.html Heinrich Wilhelm Gottfried Waldeyer-Hartz] . WhoNamedIt.
* [http://vlp.mpiwg-berlin.mpg.de/people/data?id=per357 Short biography and bibliography] in the Virtual Laboratory of theMax Planck Institute for the History of Science
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