Claude Bernard
Claude Bernard (1813-1878) was a French physician and physiologist.
Claude Bernard was a pioneering French physiologist, widely regarded as one of the founders of modern experimental medicine. Born in Saint-Julien, Rhône on 12 July 1813, Bernard initially trained in the literary arts but, after a failed attempt to enter the theatre, he turned to medicine in Paris. Under the mentorship of François Magendie (1783–1855), Bernard began a series of investigations that would redefine physiology.
Over a distinguished career, Bernard made critical discoveries in digestive physiology, neuromuscular pharmacology, and glucose metabolism. He was the first to describe the glycogenic function of the liver and introduced the concept of the milieu intérieur, a precursor to the modern understanding of homeostasis. His 1865 treatise, Introduction à l’étude de la médecine expérimentale, remains a cornerstone in the philosophy of biomedical science.
Bernard held several prestigious positions including Professor at the Collège de France, Member of the Académie des Sciences, and Imperial Senator. He was the first scientist in France to be honoured with a national funeral upon his death on 10 February 1878 in Paris.
Biography
- 1813 – Born July 12 in Saint-Julien, Rhône, France.
- 1833 – Apprenticed to pharmacist Millet in Lyon-Vaise.
- 1834 – Moved to Paris to pursue a literary career; redirected to medicine.
- 1835 – Enrolled at Faculty of Medicine, University of Paris.
- 1839 – Passed internship exam; began working with François Magendie.
- 1843 – Received MD with Thèse: Du suc gastrique et de son rôle dans la nutrition
- 1846 – Described role of pancreatic juice in fat digestion.
- 1847 – Appointed suppléant to Magendie at Collège de France.
- 1848 – Co-founded Société de Biologie.
- 1853 – Earned doctorate in zoology; demonstrated glycogenic function of liver.
- 1854 – Elected to the Académie des Sciences.
- 1855 – Succeeded Magendie as Professor at Collège de France.
- 1865 – Published Introduction à l’étude de la médecine expérimentale.
- 1867 – President of the Société de Biologie.
- 1868 – Elected to the Académie Française.
- 1869 – Appointed imperial senator.
- 1878 – Died February 10 in Paris; received a national funeral.
Medical Eponyms
Bernard-Horner syndrome (1862)
Historically eponymous in French-speaking literature for what is now widely known as Horner’s syndrome (miosis, ptosis, anhidrosis)
He described vasomotor control by the cervical sympathetic nerve in rabbits. Bernard conducted severed the cervical sympathetic nerve and meticulously documented the ensuing physiological changes. He coined the concept of “vasomotor nerves.” and is recognised in France as co-eponym: Bernard-Horner syndrome.
After the section of the cephalic branch of the great sympathetic, it is possible to observe a contraction of the pupil of the corresponding eye, accompanied by a narrowing of the palpebral opening, a retraction of the ocular globe, and an increase of the circulation, as well as of the temperature, in all parts of the corresponding face
Bernard Syndrome (1852)
Describes a constellation opposite to Horner’s: ipsilateral mydriasis, eyelid lag, increased blinking and lacrimation, vasoconstriction, and hyperhidrosis. First described in 1852–1853 during Bernard’s experimental work on sympathetic innervation in Recherches expérimentales sur le grand sympathique et spécialement sur l’influence que le section de ce nerf exerce sur la chaleur animal
Key Medical Contributions
Experimental Medicine: Bernard formalised the experimental method in medicine through controlled hypothesis-driven investigation. His 1865 publication Introduction a l’étude de la médecine expérimentale argued that physiological understanding must be grounded in reproducible laboratory findings, not speculative theory.
Milieu Intérieur and Homeostasis: Bernard introduced the concept of the milieu intérieur, the stable internal environment necessary for cellular function. This idea laid the foundation for Walter Cannon’s 1932 concept of homeostasis in The wisdom of the body.
Glycogenic Function of the Liver: In 1853, Bernard demonstrated that the liver synthesises glucose from non-carbohydrate sources, even in fasting animals. This overturned the assumption that glucose derived solely from food and clarified mechanisms of diabetes and energy storage.
Neuromuscular Pharmacology and Curare: Bernard elucidated the action of curare, showing that it paralyses motor nerves without affecting sensory transmission. This selective inhibition became fundamental to neuromuscular blockade and surgical anaesthesia.
Vasomotor Control and Thermoregulation: Bernard’s experiments on sympathetic nerve control advanced the understanding of blood flow regulation and thermal homeostasis. His lesion studies demonstrated the role of the nervous system in vasodilation and vasoconstriction.
Major Publications
- Bernard C. Du suc gastrique et de son rôle dans la nutrition. Thèses du 19e siècle. 1843
- Bernard C. Recherches expérimentales sur les fonctions du nerf spinal. 1844
- Bernard C, Huette C. Précis iconographique de médecine opératoire et d’anatomie chirurgicale. 1846 [2e 1854]
- Bernard C. De l’origine du sucre dans l’économie animale. 1848
- Bernard C. Expériences sur les manifestations chimiques diverses des substances introduites dans l’organisme. 1848
- Bernard C. Du suc pancréatique, et de son role dans les phénomènes de la digestion. 1849
- Bernard C, Huette C. Illustrated manual of operative surgery and surgical anatomy. 1852 [Translated Leveille MJ] [2e 1878]
- Bernard C. On the alteration of the taste in paralysis of the facial nerve. 1853
- Bernard C. Nouvelle fonction du foie: considéré comme organe producteur de matière sucrée chez l’homme et les animaux. 1853
- Bernard C. Recherches expérimentales sur le grand sympathique et spécialement sur l’influence que le section de ce nerf exerce sur la chaleur animal. 1852. [Bernard-Horner syndrome]
- Bernard C. Lectures on the blood. 1854 [Translated Walter F Atlee]
- Bernard C. Leçons de physiologie expérimentale appliquée à la médecine. 1855
- Bernard C. Mémoire sur le pancréas et sur la role du suc pancréatique dans les phénomèmes digestifs. 1856
- Bernard C. Leçons sur les effets des substances toxiques et medicamenteuses. 1857
- Bernard C. Leçons sur la physiologie et la pathologie du système nerveux, 1858, 2: 473-474.
- Bernard C. Leçons sur les propriétés physiologiques et les altérations pathologiques des liquides de l’organisme. 1859
- Bernard C. Des phénomènes oculo-pupillaires produits par la section du nerf sympathique cervical: ils sont indépendants des phénomènes vasculaires calorifiques de la tête. Comptes Rendus Hebdomadaires des Séances de l’Académie des Sciences. 1862, 55(9): 381-388. [Bernard-Horner syndrome]
- Bernard C. Introduction a l’étude de la médecine expérimentale. 1865
- Bernard C. An introduction to the study of experimental medicine. 1865 [Translated by Henry Copley Greene]
- Bernard C. Lecture on the physiology of the heart and its connections with the brain. 1865
- Bernard C. Leçons sur les propriétés des tissus vivants. 1866
- Bernard C. Leçons de pathologie expérimentale. 1872
- Bernard C. De la physiologie générale. 1872
- Bernard C. Leçons sur les anesthésiques et sur l’asphyxie. 1875
- Bernard C. Leçons sur le diabète et la glycogenèse animale. 1877
- Bernard C. Leçons sur les phénomènes de la vie, communs aux animaux et aux végétaux. 1878 [Bernard-Cannon homeostasis]
- Bernard C. La science expérimentale. 1878
References
Biography
- Lee JA. Claude Bernard (1813-1878). Anaesthesia. 1978 Sep;33(8):741-7.
- Schlienger J.-L. Le portrait intime de Claude Bernard (1813-1878). Médecine Des Maladies Métaboliques, 2017; 11(5): 474–479.
Eponymous terms
- Olmsted JM. Claude Bernard, 1813-1878; a pioneer in the study of carbohydrate metabolism. Diabetes. 1953 Mar-Apr;2(2):162-4.
- Bonnet P. L’historique du syndrome d Claude Bernard: le syndrome paralytique du sympathique cervical [History of the syndrome of Claude Bernard: paralytic syndrome of the cervical sympathetic nerves]. Arch Ophtalmol Rev Gen Ophtalmol. 1957 Mar;17(2):121-38.
- Pearce JM. A note on Claude Bernard-Horner’s syndrome. J Neurol Neurosurg Psychiatry. 1995 Aug;59(2):188, 191.
Eponym
the person behind the name
