Louis-Antoine Ranvier
Encyclopedia
Physician
A physician is a health care provider who practices the profession of medicine, which is concerned with promoting, maintaining or restoring human health through the study, diagnosis, and treatment of disease, injury and other physical and mental impairments...
, pathologist, anatomist
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...
and histologist
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...
, who discovered nodes of Ranvier
Nodes of Ranvier
Myelin sheath gaps or nodes of Ranvier are the gaps formed between the myelin sheaths generated by different cells. A myelin sheath is a many-layered coating, largely composed of a fatty substance called myelin, that wraps around the axon of a neuron and very efficiently insulates it...
, regularly spaced constrictions of the myelin sheath
Myelin
Myelin is a dielectric material that forms a layer, the myelin sheath, usually around only the axon of a neuron. It is essential for the proper functioning of the nervous system. Myelin is an outgrowth of a type of glial cell. The production of the myelin sheath is called myelination...
, occurying at varying intervals along the length of a nerve fiber
Axon
An axon is a long, slender projection of a nerve cell, or neuron, that conducts electrical impulses away from the neuron's cell body or soma....
.
Ranvier was born and studied medicine at Lyon
Lyon
Lyon , is a city in east-central France in the Rhône-Alpes region, situated between Paris and Marseille. Lyon is located at from Paris, from Marseille, from Geneva, from Turin, and from Barcelona. The residents of the city are called Lyonnais....
, graduating in 1865. He founded a small private research laboratory with Victor André Cornil
Victor André Cornil
Victor André Cornil, also André-Victor Cornil was a French pathologist and histologist born in Cusset, Allier.He studied medicine in Paris, earning his doctorate in 1864...
, and together they offered a course in histology to medical students. They also wrote together an influential textbook on histopathology
Histopathology
Histopathology refers to the microscopic examination of tissue in order to study the manifestations of disease...
. In 1867, Ranvier entered the Collège de France
Collège de France
The Collège de France is a higher education and research establishment located in Paris, France, in the 5th arrondissement, or Latin Quarter, across the street from the historical campus of La Sorbonne at the intersection of Rue Saint-Jacques and Rue des Écoles...
and worked as an assistant to Claude Bernard
Claude Bernard
Claude Bernard was a French physiologist. He was the first to define the term milieu intérieur . Historian of science I. Bernard Cohen of Harvard University called Bernard "one of the greatest of all men of science"...
. In 1875, he was appointed to its chair of general anatomy.
In 1878, Ranvier discovered the nodes which received his name. Other anatomical structures bearing his name are the Merkel-Ranvier cells, melanocyte
Melanocyte
-External links: - "Eye: fovea, RPE" - "Integument: pigmented skin"...
-like cells in the basal layer
Stratum germinativum
The stratum basale is the deepest layer of the five layers of the epidermis, which is the outer covering of skin in mammals. The stratum basale is a continuous layer of cells...
of the epidermis that contain catecholamine
Catecholamine
Catecholamines are molecules that have a catechol nucleus consisting of benzene with two hydroxyl side groups and a side-chain amine. They include dopamine, as well as the "fight-or-flight" hormones adrenaline and noradrenaline released by the adrenal medulla of the adrenal glands in response to...
granules; and Ranvier's tactile disks, a special type of sensory nerve
Sensory nerve
Sensory nerves are nerves that receive sensory stimuli, such as how something feels and if it is painful, smooth, rough, etc.They are made up of nerve fibers, called sensory fibers .Sensory neurons are neurons that are activated by sensory input Sensory nerves are nerves that receive sensory...
ending. In 1897, he founded the scientific journal Archives d'anatomie microscopique with Edouard-Gérard Balbiani
Edouard-Gérard Balbiani
Edouard-Gérard Balbiani was a French embryologist who was born in Port-au-Prince, Haiti. He was educated in Frankfurt and Paris. In Paris he studied natural sciences under famed zoologist Henri Marie Ducrotay de Blainville...
.
Some of his most noted students were Ferdinand-Jean Darier
Ferdinand-Jean Darier
Ferdinand-Jean Darier was a French physician, pathologist and dermatologist called the "father of modern dermatology in France".-Medical:...
, Justin Marie Jolly
Justin Marie Jolly
Justin Marie Jolly was a French hematologist and histologist born in Melun, Seine-et-Marne. He was a pioneer in the field of hematology as it pertained to the study of living tissue....
, Joaquín Albarrán
Joaquín Albarrán
Joaquín Albarrán, full name Joaquin Albarrán Maria y Dominguez was a Cuban urologist who was born in Sagua La Grande, Cuba. In 1878 he went to Paris, where he worked and studied under many renowned physicians...
, Luis Simarro Lacabra
Luis Simarro Lacabra
Luis Simarro Lacabra was a Spanish psychiatrist who was born in Rome while his parents were living in Italy....
and Fredrik Georg Gade
Fredrik Georg Gade
-Personal life:He was born in Bergen as the son of merchant Fredrik Georg Gade and his wife Ingeborg Wallem . The family originated in Lüneburg; an ancestor had migrated to Norway in the eighteenth century. The name Fredrik Georg was a family tradition...
.
He retired in 1900 to his estate in Thélys (Roanne
Roanne
Roanne is a commune in the Loire department in central France.It is located northwest of Lyon on the Loire River.-Economy:...
) and died at Vendranges
Vendranges
Vendranges is a commune in the Loire department in central France....
in 1922.