Franz Leydig
Encyclopedia
Franz von Leydig also Franz Leydig, was a German
zoologist and comparative anatomist.
(on the Tauber
river). He was the only boy of three children born to Melchior Leydig, a Catholic
and a minor public official, and Margareta, a Protestant. Leydig shared both his father’s Catholic religion and hobbies: his father was a keen gardener and beekeeper
. Leydig himself recalled later that those childhood interests began his lifelong concern with botany
and zoology
. At age 12, he acquired a simple microscope
, which he used in the majority of his free time.
Leydig studied philosophy in Munich
from 1840, and medicine
at the University of Würzburg
from 1842 under Martin Münz
(1785–1848), Schenk
, and Franz von Rinecker
(1811–1883). He received his doctorate
in medicine
at Würzburg on August 27, 1847, becoming an assistant in the physiology
department, while also teaching histology
and developmental anatomy
under Albert von Kölliker
(1817–1905). In 1848 he became prosector
at the zootomic institution in Würzburg in 1848. The following year he qualified as a lecturer, and on May 9, 1855 he was appointed professor. In the winter of 1850–1851, Leydig made a journey to Sardinia
, where he became aware of the rich marine life that was to become the subject of some of his most important researches. That journey, coupled with his early preoccupation with microscopy
, directed the course of his life’s work.
In 1857 Leydig became full professor of Zoology
and Comparative anatomy
at the University of Tübingen, and he published his Lehrbuch der Histologie des Menschen und der Tiere: his main contribution to morphology
. In the Lehrbuch, Leydig reviewed the crucial developments in the history of histology
, including the discovery and definition of the cell
by Jan Evangelista Purkyne
(1797–1869), Gabriel Gustav Valentin (1810–1883), and by Theodor Ambrose Hubert Schwann
(1810–1882), who described the cell as a vesicle containing a nucleus
in 1839. Leydig paid further tribute to other contemporary anatomists, particularly Johannes Peter Müller
(1801–1858) for his work on gland
s and emphasizing cellular doctrine for pathology
. Leydig’s book was published at the time of similar subjects – most notably Kölliker’s Handbuch der Gewebelehre des Menschen (1852) and Joseph von Gerlach
’s (1820–1896) Handbuch der allgemeinen und speciellen Gewebelehre des menschlichen Körpers... (1848). The Lehrbuch, however, gives the best account of the growth of comparative microscopical anatomy in the two decades following Schwann’s discoveries.
He became professor
of comparative anatomy
at the University of Bonn
in 1875, where he also became director of the anatomical institute, as well as, director of the zoological museum and the zoological institute. He was later made Geheimer Medizinalrat and on April 1, 1887, professor emeritus. He died on April 13, 1908, in Rothenburg ob der Tauber
, his birthplace. His wife, Katharina Jaeger, the daughter of a professor of surgery at Erlangen
, who survived him; they had no children. During his lifetime, Franz Leydig was granted many honours, including personal ennoblement, and an honorary doctorate of science from the University of Bologna
. He was a member of several medical and scientific societies, including the Royal Society of London, the New York Academy of Sciences
, the Imperial Academy of Sciences of St. Petersburg and the Royal Swedish Academy of Sciences
(1898).
zoologist and polar explorer Fridtjof Nansen
(1861–1931), who along with Wilhelm His, Sr.
(1831–1904) and Auguste-Henri Forel
(1848–1931), were the first to establish the anatomical entity of the nerve cell. Chief among Leydig's discoveries is the interstitial cell
("Leydig cells"), a body enclosed in a smooth endoplasmic reticulum and holding lipid granules and crystals, which occur adjacent to the seminiferous tubules of the testes. The cells are believed to produce the male hormone
testosterone
. Leydig had described the interstitial cells in his detailed account of the male sex organs.
The above description clearly indicates that Leydig recognized the specific morphology
of those cells: only recently, have their endocrine nature and ultrastructure been fully understood.
In addition to its historical importance, Leydig’s "Lehrbuch" is significant for his description of a large secretory cell, found in the epidermis of fish
es and larva
e amphibian
s. This mucous
cell is unusual in that it does not pour secretion over the surface of the epithelium
; Leydig believed that the cell function was to lubricate the skin, and the cell now bears his name. Leydig is also known for describing large vesicular cells that occur in the connective tissue and the walls of blood vessel
s in crustacean
s in 1883: four different types of the latter have been determined.
Germans
The Germans are a Germanic ethnic group native to Central Europe. The English term Germans has referred to the German-speaking population of the Holy Roman Empire since the Late Middle Ages....
zoologist and comparative anatomist.
Life
Franz Leydig was born on May 21, 1821, in Rothenburg ob der TauberRothenburg ob der Tauber
Rothenburg ob der Tauber is a town in the district of Ansbach of Mittelfranken , the Franconia region of Bavaria, Germany, well known for its well-preserved medieval old town, a destination for tourists from around the world. In the Middle Ages, it was an Imperial Free City...
(on the Tauber
Tauber
For the singer, see Richard Tauber.For the mathematician, see Alfred Tauber.The Tauber is a river in Franconia, Germany. It is a left tributary of the Main and is 122 km in length...
river). He was the only boy of three children born to Melchior Leydig, a Catholic
Catholic
The word catholic comes from the Greek phrase , meaning "on the whole," "according to the whole" or "in general", and is a combination of the Greek words meaning "about" and meaning "whole"...
and a minor public official, and Margareta, a Protestant. Leydig shared both his father’s Catholic religion and hobbies: his father was a keen gardener and beekeeper
Beekeeper
A beekeeper is a person who keeps honey bees for the purposes of securing commodities such as honey, beeswax, pollen, royal jelly; pollinating fruits and vegetables; raising queens and bees for sale to other farmers; and/or for purposes satisfying natural scientific curiosity...
. Leydig himself recalled later that those childhood interests began his lifelong concern with botany
Botany
Botany, plant science, or plant biology is a branch of biology that involves the scientific study of plant life. Traditionally, botany also included the study of fungi, algae and viruses...
and zoology
Zoology
Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...
. At age 12, he acquired a simple microscope
Microscope
A microscope is an instrument used to see objects that are too small for the naked eye. The science of investigating small objects using such an instrument is called microscopy...
, which he used in the majority of his free time.
Leydig studied philosophy in Munich
Munich
Munich The city's motto is "" . Before 2006, it was "Weltstadt mit Herz" . Its native name, , is derived from the Old High German Munichen, meaning "by the monks' place". The city's name derives from the monks of the Benedictine order who founded the city; hence the monk depicted on the city's coat...
from 1840, and medicine
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
at the University of Würzburg
University of Würzburg
The University of Würzburg is a university in Würzburg, Germany, founded in 1402. The university is a member of the distinguished Coimbra Group.-Name:...
from 1842 under Martin Münz
Martin Münz
Martin Münz was a German anatomist born in Bamberg.In 1812 he earned his medical doctorate from the University of Landshut, where in 1814 he earned his habilitation and in 1821 became an associate professor. Later he relocated to the University of Würzburg as a professor of anatomy, a position he...
(1785–1848), Schenk
Schenk
Schenk is a common German surname. It can refer to:* Several members of the Stauffenberg family* Lynn Schenk* Christian Schenk* Otto Schenk* Ard Schenk* Karl Schenk* Several members of the Salisbury family* Douglas Schenk* Steven Schenk* Jeff Schenk...
, and Franz von Rinecker
Franz von Rinecker
Franz von Rinecker was a German pharmacologist who was a native of Schesslitz from the district of Bamberg....
(1811–1883). He received his doctorate
Doctorate
A doctorate is an academic degree or professional degree that in most countries refers to a class of degrees which qualify the holder to teach in a specific field, A doctorate is an academic degree or professional degree that in most countries refers to a class of degrees which qualify the holder...
in medicine
Medicine
Medicine is the science and art of healing. It encompasses a variety of health care practices evolved to maintain and restore health by the prevention and treatment of illness....
at Würzburg on August 27, 1847, becoming an assistant in the physiology
Physiology
Physiology is the science of the function of living systems. This includes how organisms, organ systems, organs, cells, and bio-molecules carry out the chemical or physical functions that exist in a living system. The highest honor awarded in physiology is the Nobel Prize in Physiology or...
department, while also teaching histology
Histology
Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...
and developmental anatomy
Anatomy
Anatomy is a branch of biology and medicine that is the consideration of the structure of living things. It is a general term that includes human anatomy, animal anatomy , and plant anatomy...
under Albert von Kölliker
Albert von Kölliker
Albert von Kölliker was a Swiss anatomist and physiologist.-Biography:Albert Kölliker was born in Zurich, Switzerland. His early education was carried on in Zurich, and he entered the university there in 1836...
(1817–1905). In 1848 he became prosector
Prosector
A prosector is a person with the special task of preparing a dissection for demonstration, usually in medical schools or hospitals. Many important anatomists began their careers as prosectors working for lecturers and demonstrators in anatomy and pathology....
at the zootomic institution in Würzburg in 1848. The following year he qualified as a lecturer, and on May 9, 1855 he was appointed professor. In the winter of 1850–1851, Leydig made a journey to Sardinia
Sardinia
Sardinia is the second-largest island in the Mediterranean Sea . It is an autonomous region of Italy, and the nearest land masses are the French island of Corsica, the Italian Peninsula, Sicily, Tunisia and the Spanish Balearic Islands.The name Sardinia is from the pre-Roman noun *sard[],...
, where he became aware of the rich marine life that was to become the subject of some of his most important researches. That journey, coupled with his early preoccupation with microscopy
Microscopy
Microscopy is the technical field of using microscopes to view samples and objects that cannot be seen with the unaided eye...
, directed the course of his life’s work.
In 1857 Leydig became full professor of Zoology
Zoology
Zoology |zoölogy]]), is the branch of biology that relates to the animal kingdom, including the structure, embryology, evolution, classification, habits, and distribution of all animals, both living and extinct...
and Comparative anatomy
Comparative anatomy
Comparative anatomy is the study of similarities and differences in the anatomy of organisms. It is closely related to evolutionary biology and phylogeny .-Description:...
at the University of Tübingen, and he published his Lehrbuch der Histologie des Menschen und der Tiere: his main contribution to morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
. In the Lehrbuch, Leydig reviewed the crucial developments in the history of histology
Histology
Histology is the study of the microscopic anatomy of cells and tissues of plants and animals. It is performed by examining cells and tissues commonly by sectioning and staining; followed by examination under a light microscope or electron microscope...
, including the discovery and definition of the cell
Cell (biology)
The cell is the basic structural and functional unit of all known living organisms. It is the smallest unit of life that is classified as a living thing, and is often called the building block of life. The Alberts text discusses how the "cellular building blocks" move to shape developing embryos....
by Jan Evangelista Purkyne
Jan Evangelista Purkyne
Jan Evangelista Purkyně was a Czech anatomist and physiologist. He was one of the best known scientists of his time. His son was the painter Karel Purkyně...
(1797–1869), Gabriel Gustav Valentin (1810–1883), and by Theodor Ambrose Hubert Schwann
Theodor Schwann
Theodor Schwann was a German physiologist. His many contributions to biology include the development of cell theory, the discovery of Schwann cells in the peripheral nervous system, the discovery and study of pepsin, the discovery of the organic nature of yeast, and the invention of the term...
(1810–1882), who described the cell as a vesicle containing a nucleus
Cell nucleus
In cell biology, the nucleus is a membrane-enclosed organelle found in eukaryotic cells. It contains most of the cell's genetic material, organized as multiple long linear DNA molecules in complex with a large variety of proteins, such as histones, to form chromosomes. The genes within these...
in 1839. Leydig paid further tribute to other contemporary anatomists, particularly Johannes Peter Müller
Johannes Peter Müller
Johannes Peter Müller , was a German physiologist, comparative anatomist, and ichthyologist not only known for his discoveries but also for his ability to synthesize knowledge.-Early years and education:...
(1801–1858) for his work on gland
Gland
A gland is an organ in an animal's body that synthesizes a substance for release of substances such as hormones or breast milk, often into the bloodstream or into cavities inside the body or its outer surface .- Types :...
s and emphasizing cellular doctrine for pathology
Pathology
Pathology is the precise study and diagnosis of disease. The word pathology is from Ancient Greek , pathos, "feeling, suffering"; and , -logia, "the study of". Pathologization, to pathologize, refers to the process of defining a condition or behavior as pathological, e.g. pathological gambling....
. Leydig’s book was published at the time of similar subjects – most notably Kölliker’s Handbuch der Gewebelehre des Menschen (1852) and Joseph von Gerlach
Joseph von Gerlach
Joseph von Gerlach was a German professor of anatomy at the University of Erlangen. He was a native of Mainz, Rhineland-Palatinate. Gerlach was a pioneer of histological staining and anatomical microphotography...
’s (1820–1896) Handbuch der allgemeinen und speciellen Gewebelehre des menschlichen Körpers... (1848). The Lehrbuch, however, gives the best account of the growth of comparative microscopical anatomy in the two decades following Schwann’s discoveries.
He became professor
Professor
A professor is a scholarly teacher; the precise meaning of the term varies by country. Literally, professor derives from Latin as a "person who professes" being usually an expert in arts or sciences; a teacher of high rank...
of comparative anatomy
Comparative anatomy
Comparative anatomy is the study of similarities and differences in the anatomy of organisms. It is closely related to evolutionary biology and phylogeny .-Description:...
at the University of Bonn
University of Bonn
The University of Bonn is a public research university located in Bonn, Germany. Founded in its present form in 1818, as the linear successor of earlier academic institutions, the University of Bonn is today one of the leading universities in Germany. The University of Bonn offers a large number...
in 1875, where he also became director of the anatomical institute, as well as, director of the zoological museum and the zoological institute. He was later made Geheimer Medizinalrat and on April 1, 1887, professor emeritus. He died on April 13, 1908, in Rothenburg ob der Tauber
Rothenburg ob der Tauber
Rothenburg ob der Tauber is a town in the district of Ansbach of Mittelfranken , the Franconia region of Bavaria, Germany, well known for its well-preserved medieval old town, a destination for tourists from around the world. In the Middle Ages, it was an Imperial Free City...
, his birthplace. His wife, Katharina Jaeger, the daughter of a professor of surgery at Erlangen
Erlangen
Erlangen is a Middle Franconian city in Bavaria, Germany. It is located at the confluence of the river Regnitz and its large tributary, the Untere Schwabach.Erlangen has more than 100,000 inhabitants....
, who survived him; they had no children. During his lifetime, Franz Leydig was granted many honours, including personal ennoblement, and an honorary doctorate of science from the University of Bologna
University of Bologna
The Alma Mater Studiorum - University of Bologna is the oldest continually operating university in the world, the word 'universitas' being first used by this institution at its foundation. The true date of its founding is uncertain, but believed by most accounts to have been 1088...
. He was a member of several medical and scientific societies, including the Royal Society of London, the New York Academy of Sciences
New York Academy of Sciences
The New York Academy of Sciences is the third oldest scientific society in the United States. An independent, non-profit organization with more than members in 140 countries, the Academy’s mission is to advance understanding of science and technology...
, the Imperial Academy of Sciences of St. Petersburg and the Royal Swedish Academy of Sciences
Royal Swedish Academy of Sciences
The Royal Swedish Academy of Sciences or Kungliga Vetenskapsakademien is one of the Royal Academies of Sweden. The Academy is an independent, non-governmental scientific organization which acts to promote the sciences, primarily the natural sciences and mathematics.The Academy was founded on 2...
(1898).
Impact
Franz von Leydig's work on neural tissue influenced NorwegianNorway
Norway , officially the Kingdom of Norway, is a Nordic unitary constitutional monarchy whose territory comprises the western portion of the Scandinavian Peninsula, Jan Mayen, and the Arctic archipelago of Svalbard and Bouvet Island. Norway has a total area of and a population of about 4.9 million...
zoologist and polar explorer Fridtjof Nansen
Fridtjof Nansen
Fridtjof Wedel-Jarlsberg Nansen was a Norwegian explorer, scientist, diplomat, humanitarian and Nobel Peace Prize laureate. In his youth a champion skier and ice skater, he led the team that made the first crossing of the Greenland interior in 1888, and won international fame after reaching a...
(1861–1931), who along with Wilhelm His, Sr.
Wilhelm His, Sr.
Wilhelm His, Sr. was a Swiss anatomist and professor who invented the microtome...
(1831–1904) and Auguste-Henri Forel
Auguste-Henri Forel
Auguste-Henri Forel was a Swiss myrmecologist, neuroanatomist and psychiatrist, notable for his investigations into the structure of the human brain and that of ants. For example, he is considered a co-founder of the neuron theory...
(1848–1931), were the first to establish the anatomical entity of the nerve cell. Chief among Leydig's discoveries is the interstitial cell
Interstitial cell
Interstitial cell refers to any one of a number of different types of cells characterized by their interstitial nature Examples include:...
("Leydig cells"), a body enclosed in a smooth endoplasmic reticulum and holding lipid granules and crystals, which occur adjacent to the seminiferous tubules of the testes. The cells are believed to produce the male hormone
Hormone
A hormone is a chemical released by a cell or a gland in one part of the body that sends out messages that affect cells in other parts of the organism. Only a small amount of hormone is required to alter cell metabolism. In essence, it is a chemical messenger that transports a signal from one...
testosterone
Testosterone
Testosterone is a steroid hormone from the androgen group and is found in mammals, reptiles, birds, and other vertebrates. In mammals, testosterone is primarily secreted in the testes of males and the ovaries of females, although small amounts are also secreted by the adrenal glands...
. Leydig had described the interstitial cells in his detailed account of the male sex organs.
The above description clearly indicates that Leydig recognized the specific morphology
Morphology (biology)
In biology, morphology is a branch of bioscience dealing with the study of the form and structure of organisms and their specific structural features....
of those cells: only recently, have their endocrine nature and ultrastructure been fully understood.
In addition to its historical importance, Leydig’s "Lehrbuch" is significant for his description of a large secretory cell, found in the epidermis of fish
Fish
Fish are a paraphyletic group of organisms that consist of all gill-bearing aquatic vertebrate animals that lack limbs with digits. Included in this definition are the living hagfish, lampreys, and cartilaginous and bony fish, as well as various extinct related groups...
es and larva
Larva
A larva is a distinct juvenile form many animals undergo before metamorphosis into adults. Animals with indirect development such as insects, amphibians, or cnidarians typically have a larval phase of their life cycle...
e amphibian
Amphibian
Amphibians , are a class of vertebrate animals including animals such as toads, frogs, caecilians, and salamanders. They are characterized as non-amniote ectothermic tetrapods...
s. This mucous
Mucus
In vertebrates, mucus is a slippery secretion produced by, and covering, mucous membranes. Mucous fluid is typically produced from mucous cells found in mucous glands. Mucous cells secrete products that are rich in glycoproteins and water. Mucous fluid may also originate from mixed glands, which...
cell is unusual in that it does not pour secretion over the surface of the epithelium
Epithelium
Epithelium is one of the four basic types of animal tissue, along with connective tissue, muscle tissue and nervous tissue. Epithelial tissues line the cavities and surfaces of structures throughout the body, and also form many glands. Functions of epithelial cells include secretion, selective...
; Leydig believed that the cell function was to lubricate the skin, and the cell now bears his name. Leydig is also known for describing large vesicular cells that occur in the connective tissue and the walls of blood vessel
Blood vessel
The blood vessels are the part of the circulatory system that transports blood throughout the body. There are three major types of blood vessels: the arteries, which carry the blood away from the heart; the capillaries, which enable the actual exchange of water and chemicals between the blood and...
s in crustacean
Crustacean
Crustaceans form a very large group of arthropods, usually treated as a subphylum, which includes such familiar animals as crabs, lobsters, crayfish, shrimp, krill and barnacles. The 50,000 described species range in size from Stygotantulus stocki at , to the Japanese spider crab with a leg span...
s in 1883: four different types of the latter have been determined.