Louis-Antoine Ranvier (2 October 1835 – 22 March 1922) was a French

physician A physician (American English), medical practitioner (Commonwealth English), medical doctor, or simply doctor, is a health professional who practices medicine, which is concerned with promoting, maintaining or restoring health through th ...

pathologist Pathology is the study of the causal, causes and effects of disease or injury. The word ''pathology'' also refers to the study of disease in general, incorporating a wide range of biology research fields and medical practices. However, when us ...

anatomist Anatomy () is the branch of biology concerned with the study of the structure of organisms and their parts. Anatomy is a branch of natural science that deals with the structural organization of living things. It is an old science, having its ...

and

histologist Histology, also known as microscopic anatomy or microanatomy, is the branch of biology which studies the microscopic anatomy of biological tissues. Histology is the microscopic counterpart to gross anatomy, which looks at larger structures vis ...

, who discovered the

nodes of Ranvier In neuroscience and anatomy, nodes of Ranvier ( ), also known as myelin-sheath gaps, occur along a myelinated axon where the axolemma is exposed to the extracellular space. Nodes of Ranvier are uninsulated and highly enriched in ion channels, al ...

, regularly spaced discontinuities of the

myelin sheath Myelin is a lipid-rich material that surrounds nerve cell axons (the nervous system's "wires") to insulate them and increase the rate at which electrical impulses (called action potentials) are passed along the axon. The myelinated axon can be l ...

, occurring at varying intervals along the length of a nerve fiber.

Career

Ranvier was born and studied medicine at

Lyon Lyon,, ; Occitan: ''Lion'', hist. ''Lionés'' also spelled in English as Lyons, is the third-largest city and second-largest metropolitan area of France. It is located at the confluence of the rivers Rhône and Saône, to the northwest of t ...

, graduating in 1865 from the Ecole Préparatoire de Médecine et de Pharmacie. He moved to Paris after receiving the internship of Parisian hospitals. Here he founded a small private research laboratory on Rue Christine along with fellow intern

Victor André Cornil Victor André Cornil, also André-Victor Cornil (17 June 1837 – 13 April 1908) was a French pathologist, histologist and politician born in Cusset, Allier. Biography He studied medicine in Paris, earning his doctorate in 1864. In 18 ...

, and together they later offered a course in histology to medical students which involved the careful examination of tissues under a microscope. Their course was unique in the time as microscopy had not been viewed favourably in medicine especially by Henri Ducrotay de Blainville (1777-1850) and

Auguste Comte Isidore Marie Auguste François Xavier Comte (; 19 January 1798 – 5 September 1857) was a French philosopher and writer who formulated the doctrine of positivism. He is often regarded as the first philosopher of science in the modern sense ...

(1798-1857). Their histology course material became an influential textbook on

histopathology Histopathology (compound of three Greek words: ''histos'' "tissue", πάθος ''pathos'' "suffering", and -λογία '' -logia'' "study of") refers to the microscopic examination of tissue in order to study the manifestations of disease. Spe ...

. In 1867, Ranvier entered the

Collège de France The Collège de France (), formerly known as the ''Collège Royal'' or as the ''Collège impérial'' founded in 1530 by François I, is a higher education and research establishment (''grand établissement'') in France. It is located in Paris ne ...

and worked as an assistant to

Claude Bernard Claude Bernard (; 12 July 1813 – 10 February 1878) was a French physiologist. Historian I. Bernard Cohen of Harvard University called Bernard "one of the greatest of all men of science". He originated the term ''milieu intérieur'', and the a ...

. In 1875, he was appointed to its chair of general anatomy. Ranvier_1882

In 1878, Ranvier discovered the nodes along nerves which received his name. He conducted experiments on nerve growth, repair, and regeneration. Other anatomical structures bearing his name are the Merkel-Ranvier cells,

melanocyte Melanocytes are melanin-producing neural crest-derived cells located in the bottom layer (the stratum basale) of the skin's epidermis, the middle layer of the eye (the uvea), the inner ear, vaginal epithelium, meninges, bones, and heart. ...

-like cells in the

basal layer The ''stratum basale'' (basal layer, sometimes referred to as ''stratum germinativum'') is the deepest layer of the five layers of the epidermis, the external covering of skin in mammals. The ''stratum basale'' is a single layer of columnar or ...

of the

epidermis The epidermis is the outermost of the three layers that comprise the skin, the inner layers being the dermis and hypodermis. The epidermis layer provides a barrier to infection from environmental pathogens and regulates the amount of water rele ...

that contain

catecholamine A catecholamine (; abbreviated CA) is a monoamine neurotransmitter, an organic compound that has a catechol (benzene with two hydroxyl side groups next to each other) and a side-chain amine. Catechol can be either a free molecule or a subst ...

granules; and Ranvier's tactile disks, a special type of

sensory nerve A sensory nerve, or afferent nerve, is a general anatomic term for a nerve which contains predominantly somatic afferent nerve fibers. Afferent nerve fibers in a sensory nerve carry sensory information toward the central nervous system (CNS) fr ...

ending. In 1897, he founded the scientific journal ''Archives d'anatomie microscopique'' with Edouard-Gérard Balbiani. Some of his most notable students included Ferdinand-Jean Darier,

Justin Marie Jolly Justin Marie Jolly (August 6, 1870 – February 1, 1953) 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. He studied medicine ...

Joaquín Albarrán Joaquín Albarrán, full name Joaquin Maria Albarrán y Dominguez (May 9, 1860 – January 17, 1912) was a Cuban urologist born in Sagua La Grande, Cuba. He received the Order of the Legion of Honour of France. Biography He studied medicine in Hav ...

Luis Simarro Lacabra Luis Simarro Lacabra (6 January 1851 – 19 June 1921) was a Spanish neurologist who was born in Rome while his parents were living in Italy. Career He studied medicine in Valencia and Madrid, and in 1877 was appointed director of the San ...

Joseph-Louis Renaut Joseph-Louis Renaut (7 December 1844 – 26 December 1917) was a French physician, anatomist, and histologist. A student of Louis-Antoine Ranvier, he served as professor of anatomy and histology at the faculty of medicine in Lyons. Renaut bodies or ...

, and Fredrik Georg Gade.

Retirement

Ranvier retired in 1900 to his estate in Thélys (

Roanne Roanne (; frp, Rouana; oc, Roana) is a commune in the Loire department, central France. It is located northwest of Lyon on the river Loire. It has an important Museum, the ''Musée des Beaux-arts et d'Archéologie Joseph-Déchelette'' (Fren ...

) and died at Vendranges in 1922.

Bibliography

* Ranvier, Louis-Antoine and Victor André Cornil. 1869. ''Manuel d'histologie pathologique''. Paris * Ranvier, Louis-Antoine. 1875–1882.
Traité technique d'histologie
'. Paris: F. Savy * Ranvier, Louis-Antoine. 1878. ''Leçons sur l'histologie du système nerveux'', par M. L. Ranvier, recueillies par M.Ed. Weber. Paris * Ranvier, Louis-Antoine. 1880. ''Leçons d'anatomie générale sur le système musculaire'', par L. Ranvier, recueillies par M. J. Renaut. Paris * Ranvier, Louis-Antoine. 1885. ''Exposé des titres et des travaux de M. L. Ranvier''. Paris

References

External links

Ranvier, Louis-Antoine
at The Virtual Laboratory {{DEFAULTSORT:Ranvier 1835 births 1922 deaths 19th-century French physicians French anatomists French pathologists Members of the French Academy of Sciences