Magendie, François

views updated May 14 2018

MAGENDIE, FRANçOIS

(b. Bordeaux, France, 6 October 1783; d. Sannois, Seine-et-Oise, france, 7 October 1855)

Physiology, medicine.

Magendie was a son of Antoine Magendie, a surgeon, and Marie Nicole de Perey. He had a younger brother, Jean-Jacques, whose name testifies to the admiration their father, an ardent republican, had for the deas of Rousseau. The two boys were brought up in accord with Rousseau’s pedagogical precepts: the emphasis was on their personal independence and not the instruction they received. As Pierre Flourens wrote in his éloge of François Magendie: “The new Émile, absolutely given over to himself, went about as he pleased in a liberty that very closely resembled abandonment.” In 1791, swept along by the Revolution, the Magendie family moved to Paris, where the father devoted himself more to politics than to medicine. The death of his mother in 1792 and his father’s activities on Revolutionary committees threw Magendie still further upon his own intellectual resources. Having reached the age of ten without having attended school or having learned to read and write, at his own wish he entered elementary school, where he made very rapid progress. At the age of fourteen he won the grand prize in a national contest for an essay on knowledge of the rights of man.

At sixteen, too young to be admitted to the École de Santé, Magendie became an apprentice at a Paris hospital, where the surgeon Alexis Boyer, a friend of his father’s, accepted him as a pupil and entrusted him with the anatomical dissections. In 1803 Magendie passed the examination required for an interne des hôpitaux and entered the Hôpital Saint-Louis as a medical student. In 1807 he became an assistant in anatomy at the École de Médecine and gave courses in anatomy and physiology. He received his medical degree in Paris on 24 March 1808 after defending a dissertation entitled Essai sur les usages du voile de palais avec quelques propositions sur la fracture du cartilage des côtes. Magendie’s studies reflect the chaotic situation of teaching in France during the period. A liberal education in his childhood, a practically oriented apprenticeship in medicine, the astonishing experience of the successive collapses of academic and doctrinal systems—all these combined to strengthen in Magendie a love of facts and a contempt for words, theories, and social conventions, as well as a rude frankness and a truly exceptional independence of judgment.

After his thesis Magendie’s first publication was an article of a theoretical, not to say doctrinal, character. It appeared in the Bulletin des sciences médicales, which, published by the Société Médicale d’émulation, did its utmost to glorify the memory of Bichat; yet Magendie’s memoir was a harsh attack on the fundamental ideas of this intellectual master of French physicians. Magendie asserted: “[The] majority of physiological facts must be verified by new experiments and this is the only means of bringing the physics of living bodies out of the state of imperfection in which it lies at present” (Bulletin des sciences médicales, 4 [1809,] 147). According to Magendie, the biological sciences had remained behind the physical sciences because they utilized complicated ideas and preconceptions to explain facts which very often were not themselves established with certainty. Magendie still accepted the concept of a vital force (considering it a supposition that served merely to bring together in a single term all the characteristics proper to life), but he proposed “to abolish the two vital properties known under the names of animal sensibility and animal contractility and to consider them as functions” (op. cit. p. 166).

Further, he condemned Bichat’s attempt to increase the number of vital properties by distinguishing them according to the organic tissues. In Magendie’s view, physiology should explain the two phenomena essential to life—nutrition and movement—through reducing them to the organization of living beings and of their parts. Magendie’s profession of faith is, in fact, the fundamental dogma of modern biology: “Two living bodies having the same organization will display the same vital phenomena; two living bodies having different organizations will display vital phenomena the diversity of which will always be in direct proportion to the difference in organization” (op. cit., p. 159).

The gnoseological optimism of this youthful piece was rapidly replaced by a certain skepticism and a growing distrust of all theoretical generalization. Although he later honored Bichat by preparing his two major works for publication, Magendie furnished these editions with ample commentaries praising Bichat the experimenter but treating with irony all attempts at a systematic explanation of vital phenomena. The influence of the philosophy of the Idéologues had prevailed over the vitalist doctrines of the Montpellier school; and Magendie, having taken an aversion to all theories, made an extraordinary effort during most of his life to discover and collect the “facts” and refused, to the extent this was possible, to interpret them. “I compare myself,” he said to Claude Bernard, “to a ragpicker: with my spiked stick in my hand and my basket on my back, I traverse the field of science and I gather what I find” (C. Bernard, Magendie, p. 13). This was, of course, an illusion: Magendie made his discoveries on the basis of certain theoretical considerations and within the framework of a rather well defined philosophy of biology. But this illusion was particularly important at a moment in the history of physiology when it was necessary to replace excessive speculation with recourse to the “facts”—that is, with recourse to the experimental method. In this sense Bernard was perfectly right when he stressed that “M. Magendie is not one of those men concerning whom one can give a sufficient idea simply by enumerating their works or by pointing out the discoveries with which they have enriched science” and that, for the historian of science, Magendie’s principal merit consisted in the influence he exerted in orienting physiology toward experimental investigations.

In 1809 Magendie presented to the Académie des Sciences and to the Société Philomatique the results of his first experimental work, which he carried out in collaboration with the botanist and physician A. Raffeneau-Delile. In a series of ingenious experiments on various animals, the two investigators studied the toxic action of several drugs of vegetable origin, particularly of upas, nux vomica, and St.-Ignatius’s bean. As Olmsted observes, these experiments mark the beginning of modern pharmacology. For the first time an experimental comparison was made of the similar effects produced by drugs of different botanical origin. Magendie held that the toxic or medicinal action of natural drugs depends on the chemical substances they contain, and it should be possible to obtain these substances in the pure state. As early as 1809 he suspected the existence of strychnine, later isolated, in accord with his predictions, by P. J. Pelletier (1819). Moreover, in 1817, in collaboration with Pelletier, Magendie discovered emetine, the active principle of ipecac. Immediately after the isolation of strychnine he demonstrated that it produces exactly the same type of poisoning as do certain vegetable drugs.

The experiments of 1809 enabled Magendie and Raffeneau-Delile to affirm that upas and nux vomica, which produce generalized convulsions and tetanus, must act on the spinal marrow and, in fact, must stimulate it very strongly. Sectioning the medulla— separating it from the brain—does not suppress the symptoms of the poisoning, whereas destruction of the medulla eliminates them completely. The character of the symptoms was found to be independent of the way in which the poison entered the organism, but the latter circumstance did influence the rapidity with which the first spasms began. Magendie thus formulated the principle of local action: A toxic or: medicinal substance acts solely in terms of its direct contact with an effector organ. This principle obliged physiologists to accord great importance to the study of the absorption and transport of poisons and medicines in the organism.

At the beginning of the nineteenth century the generally accepted view was that absorption takes place exclusively through lymphatic vessels. This theory, elaborated by John Hunter and reinforced by Bichat’s teaching, had replaced Haller’s opinion, according to which food and all other substances are absorbed through the veins. Magendie, however, demonstrated the existence of two absorption paths. He conducted a classic experiment in which a dog was poisoned following the introduction of the toxic substance into a limb that was connected to the body only by a blood vessel, or even only by a quill. Magendie concluded that the absorption of liquids and semiliquids is not a vital and physically inexplicable function of the lymphatics by a simple physicochemical phenomenon of the imbibition of tissues and of passage trough vascular walls.

In 1811 Magendie was appointed anatomy demonstrator at the Faculté de Médecine of Paris, and for three years he taught anatomy and surgery. He displayed unusual skill during his operations at the École Pratique. Meanwhile, his rude behavior precipitated a conflict with the professor of anatomy, François Chaussier. The professor of surgery, Guillaume Dupuytren, saw Magendie as a dangerous rival and created difficulties for him at the Faculté de Médecine. In 1813 Magendie resigned from his post as demonstrator, opened an office as a practicing physician, and organized a private course in physiology. In his éloge Flourens speaks of a veritable “volte-face”: in his opinion, Magendie suddenly buried all his ambitions as an anatomist and surgeon in order to devote himself to experimental physiology. Whether it was a long-considered project or simply an impulsive act cannot be known; in any case his private courses, featuring experiments on living animals, aroused the curiosity of the medical public and soon enjoyed a large success. It is from this moment that Claude Bernard dated the beginning of the “new physiology.” “Magendie,” he wrote, “joined example to precept. He undertook private courses of experimental physiology based on vivisections. He attracted numerous students, among whom were a great many foreigners. It was from this center that the young physiologists carried the seeds of the new experimental physiology into the neighboring schools, where it then developed with such prodigious rapidity” (Rapport sur le progrés et la marche de la physiologie en France, p.7).

Magendie’s teaching was not only oral. The interest evoked by his courses led him to write Précis élémentaire de physiologie, in which, just as in his lectures, experimental demonstration replaced theoretical discussion as much as possible. He thus created a new type of physiology textbook: philosophical deductions founded on anatomy and on doctrinal suppositions were greatly reduced in favor of simple and precise descriptions of experimental facts. The first volume of the Précis was published in 1816, the second in 1817. This work, which went through four French editions and was translated into several other languages, including English and German, exerted a very profound influence on physicians and biologists during the first half of the nineteenth century.

In the introduction to his Précis, Magendie explained and justified his methods of investigating vital phenomena. Without abandoning his vitalist position (that is, he still accepted that “corps vitalist differ from “corps bruts” both in their form and composition and in certain supplementary laws that govern them), Magendie criticized the ontological interpretations of soul and of vital principle. He rejected as a dangerous illusion the methodological analogy between the vital force and Newtonian gravitation. For him, vital force would remain an empty term as long as it was impossible to link it, on the example of universal attraction, to a precise law. According to Magendie, the laws of life, even if they possess their own character, cannot be in contradiction with the physicochemical laws. The first task of physiology was to push the physical analysis of vital phenomena as far as possible. In theory and in practice, therefore, Magendie preached an empirical reductionism.

Between 1813 and 1821 Magendie made a great many discoveries in almost all the fields of research that then constituted physiology. Among these were proof of the passive role of the stomach in vomiting; explanation of the mechanism of deglutition; experiments on alimentation with nonnitrogenous substances (demonstration of the mammals’ need for a protein supply and the first experimental production of an avitaminosis); experiments on digestive properties of pancreatic juice; proof of the liver’s decisive role in detoxification processes; demonstration of the hemodynamic importance of the elasticity of the arteries; discovery of emetine and experiments on the toxic action of hydrocyanic acid; comparative anatomical investigations clarifying the mechanism of absorption; and new observations following vivisections of cranial nerves. Magendie was also the first to make comparative nutrition experiments with chemically pure substances.

Although Magendie was interested primarily in experimental physiology, he did not neglect medical practice. For many years he suffered from not being on a hospital staff, which would have facilitated the clinical study of new medicines. In 1818, following a competitive examination, he was named to the Bureau Central des Hôpitaux Parisiens; but until 1826 he had no official hospital assignment and had to rely on the understanding of his friend Henri Husson in order to observe treatments and to give a clinical course at the Hôtel-Dieu. In 1819 he was requested to give a course at the Athénée Royal. In 1821 he published the first edition of his Formulaire pour la préparation et l’emploi de plusieurs nouveaux médicaments, a therapeutical manual much used by physicians. Magendie introduced into medical practice a series of recently discovered alkaloids; strychnie, morphine, brucine, codeine, quinine, and veratrine. He also generalized the therapeutic use of iodine and bromine salts. Contrary to the dominant opinion among the older physicians, Magendie favored the use of chemical substances over that of natural drugs and, in addition, had great confidence in pharmacological experiments on animals. He did not hesitate to test on himself all the substances that were shown to be harmless in the animal experiments.

In 1821 Magendie was elected to the Académie des Sciences and the Académie Royale de Médecine. In the same year he founded the Journal de physiologie expérimentale, the first periodical devoted exclusively to physiology. Starting with the second volume he added the words et pathologie to the title. Convinced that pathology is essentially “the physiology of the sick organism,” Magendie already envisaged a complete reform of medicine by establishing it upon the experimental study of the vital functions; the idea of this project was later brilliantly defended and developed by his disciple Claude Bernard.

It was in his Journal that Magendie published the results of his investigations on the physiology of the nervous system and on the cerebrospinal fluid. The discovery of the Bell-Magendie law (1822) was the source of a distressing dispute over the parts played by Charles Bell and by Magendie in distinguishing the motor and sensory roots of the medulla. The historical documents relating to this subject do not appear to contradict Magendie’s final claims:

In sum, Charles Bell had had, before me, but unknown to me, the idea of separately cutting the spinal roots; he likewise discovered that the anterior influences muscular contractility more than the posterior does. This is a question of priority in which I have, from the beginning, honored him. Now, as for having established that these roots have distinct properties, distinct functions, that the anterior ones control movement, and the posterior ones sensation, this discovery belongs to me [Comptes rendus … des séances de l’Académie des sciences, 24 (1847), 320].

Although it is possible that, from the start of his research on the spinal nerves, Magendie knew of Bell’s general idea through the latter’s assistant, John Shaw, it is nonetheless certain that the clear statement and the experimental verification of the law in question belongs to him. This discovery, of fundamental importance for neurophysiology, was completed by Magendie and Claude Bernard with the experimental explanation of an apparent exception known as sensiblité récurrente (1847).

In 1823 Magendie produced experimentally and described the rigidity that follows decerebration; he provided the first proof of the cerebellum’s role in maintaining the equilibrium of the organism; and he cut the fifth pair of cranial nerves within the cranium itself, demonstrating the direct responsibility of these nerve structures for the sense of touch and their indirect trophic role in the maintenance of the function of the other senses. In 1824 he observed the circular movement (“mouvement de manège”) that occurs in the rabbit following the section of the cerebellar peduncle. This experiment was the point of departure for Bernard’s discovery of the “piqûre sucrèe” and, later, of Jacques Loeb’s experiments on the rotary movements of animals. During the period 1824–1828 Magendie made many discoveries concerning the origin, composition, and circulation of the cerebrospinal fluid. He showed that the brain cavities communicate freely with the spinal subarachnoid space and described the medial foramen in the roof of the fourth ventricle (foramen Magendie). Through severing the various branches of the facial never, Magendie succeeded in definitively banishing the ancient hypothesis of the “nervous fluid.”

During a trip to England in 1824, when he was a guest of William Hyde Wollaston’s, Magendie gave several public demonstrations of his method of the experimental section of cranial nerves of living dogs. The cruel side of his experiments provoked an antivivisectionist campaign. Although powerful in Great Britain, this struggle for the protection of animals found no echo in France. Some colleagues, however, reproached Magendie for having experimented on sick people—that is, for having performed operations the goal of which was essentially scientific and not therapeutic. Such proceedings are described in Magendie’s publications, but they were never really dangerous or mutilating. Particularly noteworthy are his experiments on the human retina, which could have led him, if he had a taste for theoretical generalization, to the discovery of the law of the specific energy of the senses.

In 1830 Magendie finally obtained the directorship of a hospital department, the women’s ward at the Hôtel-Dieu. Despite everything that one could say concerning his gruff manners toward his colleagues and his cruelty to animals, contemporary testimony agrees on the gentleness, patience, and understanding with which he treated his hospital patients. On 4 April 1831 he replaced J. C. A. Récamier in the chair of medicine at the Collége de France. It was not without some difficulty that the medical instruction there was changed in style and in substance. Instead of expounding doctrines, Magendie gave public demonstrations of the experimental method; instead of teaching clinical medicine as it was practiced at the patient’s bedside, he concentrated on the presentation of physiological and pathological knowledge derived from studies made on animals. Nevertheless, his initial lectures at the Collège de France were devoted to a medical problem of current concern: cholera. Magendie had just made a trip to England, to Sunderland, where he had been able to follow closely an epidemic of this disease. After his return to Paris, cholera broke out there. Magendie fought it courageously and devised a good symptomatic treatment, but he was seriously mistaken in asserting that it was not contagious. He also denied the contagiousness of yellow fever and opposed quarantine.

This error had dire consequences, in particular after 1848, when Magendie was appointed head of the Advisory Committee on Public Hygiene. Even though he belonged to the anticontagionist camp, Magendie had made a positive contribution to the study of infection: he had demonstrated experimentally that the saliva of rabid dogs contains a contagious principle. He also observed the effects of intravenous injections of putrid blood and led B. Gaspard to study the phases of sepsis by the experimental method (1822– 1823). Another serious error of Magendie’s was his impassioned activity against surgical anesthesia induced by ether (1847).

From 1832 to 1838 Magendie delivered his famous lectures on the physical phenomena of life at the Collège de France. These lectures were dominated by two main ideas: to extend as far as possible the purely physical explanation of vital phenomena and to base medical practice on the certain knowledge of normal and pathological physiology. Among the discoveries belonging to this period, the most interesting is that concerning the phenomenon later called anaphylaxis: Magendie ascertained that a second injection of egg white results in the death of rabbits that had tolerated perfectly well the first injection of the substance.

Beginning in 1838 Magendie’s lectures dealt successively with the physiology of the nervous system, the dynamics of the circulation of the blood, the cerebrospinal fluid, and nutrition. In collaboration with Poiseuille, he carried out fundamental studies on arterial pressure and demonstrated the hemodynamic role of the elasticity of the major arteries. He also showed the very poor nutritive value of gelatin, until then utilized in the hospitals as an inexpensive food. In 1846 Magendie demonstrated that the presence of sugar in the blood is not necessarily a pathological phenomenon. These experiments on glycemia served Claude Bernard as the starting point of the research that culminated in his discovery of the glycogenic function of the liver.

Through his marriage to Henriette Bastienne de Puisaye in 1830, Magendie had acquired an estate in Sannois, Seine-et-Oise. There he led a very happy family life. Yielding to the fatigue brought on by approaching old age, he withdrew more and more to his country house, left the Hôtel-Dieu (1845), and had Bernard substitute for him at the Collège de France (1847). At Sannois he undertook experiments in plant physiology with a view to improving agricultural yield. He died probably of a heart ailment.

Balzac masterfully characterized Magendie, under the barely disguised name “docteur Maugredie,” in La peau de chagrin (1831): “a distinguished intellect, but skeptical and contemptuous, who believed only in the scalpel” and who “claimed that the best medical system was to have none at all and to stick to the facts.”

BIBLIOGRAPHY

I. Original Works. Megendie’s principal publications are “Quelques idées générales sur les phénoménes particuliers aux corps vivants,” in Bulletin des sciences médicales, 4 (1809), 145–170; “Examen de l’action de quelques végétaux sur la moelle épiniére,” in Nouveau bulletin scientifique de la Société philomatique, 1 (1809), 368–405; Mémoire sur le vomissement (Paris, 1813); Précis élémentaire de physiologie, 2 vols. (Paris, 1816–1817); 2nd ed., rev., 1825; 3rd ed., rev., 1834; 4th ed., 1836); “Mémorie sur les propriétés nutritives des substances qui ne contiennent pas d’azote,” in Bulletin de la Société philomatique, 4 (1816), 137; “Mémoire sur l’émétine et sur les trois espéces d’ipécacuanha,” in Journal général de médecine, de chirurgie et de pharmacie, 59 (1817), 223–231, written with P.J. Pelletier; Formulaire pour la préparation et l’emploi de plusieurs nouveaux médicaments, tels que la noix vomique, la morphine, etc. (Paris, 1821); “Expériences sur les fonctions des racines des nerfs rachidiens,” in Journal de physiologie expérimentale et de pathologie,2 (1822), 276–279; “Expériences sur les fonctions des racines des nerfs que naissent de la moelleépinière,” ibid., pp. 366–371; “Mémoire sur les fonctions de quelques parties du systéme nerveux,” ibid., 4 (1825), 399–407; “Mémoire sur un liquide qui setrouve dans le crâne et le canal vertébral de l’homme et des animamux mammifères,” ibid., 5 (1824), 27–37, and 7 (1827), 1–29, 66–82; Lectures on the Blood (Philadelphia, 1839); Leçons sur les fonctions et les maladies du système nerveux, 2 vols. (Paris, 1839–1841); Phénomènes physiques de la vie, 4 vols. (Paris, 1842); and Recherches physiologiques et cliniques sur le liquide céphalo-rachidien ou cérébrospinal (Paris, 1842).

II . Secondary Literature. Among the obituary notices containing information on Magendie’s life and work, of special interest are F. Dubois, “éloge de M. Magendie,” in Mémoires de l’ Académie impériale de médecine de Paris, 22 (1858), 1–36; and P. Flourens, éloge historique de François Magendie (Paris, 1858), see also E. Littré, “Magendie,” in Journal des débates (30 May and 28 June 1856); and A. E. Serres, Funérailles de Magendie (Paris, 1855). In a lecture at the Collège de France, Claude Bernard analyzed the historical influence, philosophical position, and character of his teacher: François Magendie (Paris, 1856).

For biograPhies of Magendie, see M. Genty, “François Magendie,” in Les biographies médicales, IV (1935), 113– 144; P. Menetrier, “Documents inédits concernant Magendie,” in Bulletin de la Société française d’histoire de la médecine, 20 (1926), 251–258; the best modern biographical study is undoubtedly J. M. D. Olmsted, François Magendie: Pioneer in Experimental Physiology and Scientific Medicine in XIX Century France (New York, 1944).

Concerning Magendie’s epistemological views and general ideas one should consult T. S. Hall, Ideas of Life and Matter (Chicago, 1969), II, 245–251; and O. Temkin, “The Philosophical Background of Magendie’s Physiology,” in Bulletin of the History of Medicine, 20 (1946), 10–35. On the pharmacological experiments see M. P. Earles, “Early Theories of Mode of Action of Drugs and Poisons,” in Annals of Science, 17 (1961), 97–110. The controversy between Bell and Magendie over the discovery of the properties of the spinal nerves was well analyzed by C. Bernard, Rapport sur le progrès et la marche de la physiologie en France (Paris, 1867), pp. 10–14, 154–158; and by A. Flint, Jr., “Considérations historiques sur les propriétés des racines rachidiennes,” in Joural de l’anatomie et de la physiologie…, 5 (1868), 520–538, 577–592. A recent restatement of the issue can be found in E. Clarke and C. D. O’Mally, The Human Brain and Spinal Cord (Berkeley-Los Angeles, 1968), pp. 296–303.

M. D. Grmek

Magendie, Francois

views updated Jun 08 2018

Francois Magendie

French physiologist Francois Magendie (1783–1855) made pioneering efforts in the medical fields of physiology, pharmacology, pathology, and nutrition. More interested in facts than theory, his experiments led to such innovations as the introduction of various drugs into medical practice and the Bell–Magendie Law regarding the functioning of spinal nerves. Among his other contributions were his early description of cerebrospinal fluid and a delineation of a foramen (small opening) in the brain that later came to bear his name.

Early Life

Magendie was born the eldest of two sons to Antoine Magendie and Marie Nicole de Perey on October 6, 1783, in Bordeaux, France. His father was a surgeon who was a devotee of Utopian philosopher Jean–Jacques Rousseau (1712–1778), even naming his youngest son after him. Magendie's father was also an ardent proponent of the imminent French Revolution (1789–1799). The Magendie boys were reared in accordance with Rousseau's teachings in that their individual independence was prized more highly than the benefits of outside instruction. This was, unsurprisingly, both a help and a hindrance to them, as it fostered an ability to think for themselves, while restricting their access to a basic education.

With the revolution in full force in 1791, the Magendie family relocated to Paris so that Antoine Magendie could immerse himself in politics more completely. Magendie's mother died the following year, depriving her sons further of the minimal intellectual guidance and stimulation they had known. At the age of ten, Magendie, who had not yet learned to read or write, finally took matters into his own hands and insisted on going to school for the first time. There, he combined his innate intelligence with his unorthodox upbringing and excelled.

As the revolution was winding down, Magendie was apprenticed to surgeon Baron Alexis de Boyer (1757–1833) at the Hotel–Dieu. Just 16 years old, he was allowed to indulge his interest in anatomy by participating in dissections. It was a practical training that was well–suited to the young man's temperament, and helped nurture in him an affinity for facts over theory. In 1803, Magendie passed the entrance examination for medical school and began traditional medical training. He received his M.D. in Paris on March 24, 1808.

Personality Problems

Shortly after obtaining his degree, Magendie began to ruffle feathers in the medical community. His first published article was a severe critique of Marie Francois Xavier Bichat's (1771–1802) basic premises, and appeared in the Bulletin of Medical Science. Bichat was one of the icons of French physicians.

Magendie's abrupt style was to serve him ill throughout his career. Often seen as vain, rude, and contemptuous among his fellows, his personality often hindered his advancement and sometimes cost him positions. For example, all his surgical skill later displayed during his brief time at the Faculty of Medicine of Paris could not override the conflicts with the professors of anatomy (Francois Chaussier) and surgery (Guillaume Dupuytren) that caused him to resign his post as anatomy demonstrator after only two years. For all the hostility he engendered, however, Magendie's innovative work and electrifying insights could not be denied by even his harshest detractors.


Physiology, Pharmacology, and the Lymphatic Myth

Physiology was defined by the Microsoft Encarta Online Encyclopedia as a, "study of the physical and chemical processes that take place in living organisms during the performance of life functions. It is concerned with such basic activities as reproduction, growth, metabolism, excitation, and contraction as they are carried out within the fine structure, the cells, tissues, organs, and organ systems of the body." During his medical education, Magendie transferred his primary allegiance from anatomy to physiology, especially with regard to the central nervous system, cerebrospinal fluid, and the spinal nerves, and he went on to be considered one of the forefathers of experimental physiology. Despite all this, Magendie's first important study had a significant impact on the field of modern pharmacology instead.

In 1809, just a year out of medical school, Magendie presented the finding of his first experimental study, conducted with botanist and physician Alire Raffeneau–Delille (1778–1850). They ran a series of experiments to discover the consequences of various plant–derived drugs on the body. This was important to pharmacology in that it was the first time a comparison was made of the analogous effects produced by drugs of different botanical origins. It was Magendie's contention that the action of a natural drug was dependent on its chemical substance, and that that active ingredient must be attainable in its pure state. (He was later proven correct with the isolation, for instance, of strychnine in 1819 and his own detection of emetine, from ipeac, in 1817). But these remarkable insights were not all the experiments revealed. They also debunked the prevailing view that absorption took place solely through the lymphatic system. By introducing a poison into an animal's system through either a blood vessel or quill, Magendie was able to demonstrate that absorption was instead achieved through the bloodstream and the skin. Beyond its invaluable educational value, such research eventually led to the introduction of several new drugs, including morphine, codeine, and quinine.


Teacher and Physician

In 1811, Magendie took the short–lived position of anatomy demonstrator at the Faculty of Medicine of Paris mentioned above. He also taught anatomy, physiology, and surgery there. When he resigned in 1813, Magendie opened his own medical practice and taught physiology privately. For quite some time, perhaps partly because of his outsider status in the medical community, he was unable to find an official post on a hospital staff. This limited his ability to conduct clinical studies and observe treatments, among other professional inconveniences. In 1818, Magendie was appointed to the Central Bureau of Parisian Hospitals, but it was not until 1826 that he was at last given a formal hospital assignment, at the Salpetriere. He was then named director of the women's ward at his alma mater, the Hotel–Dieu, in 1830. Finally, on April 4, 1831, Magendie found his niche as the chair of medicine at the College of France. It was there he established the first medical school laboratory, and would later come to know the talented protégé, Claude Bernard (1813–1878), who was destined to, in some respects, eclipse him.

It is worth noting that Magendie's infamous personality flaws were seldom in evidence around his patients, among whom he had a fast reputation for great sympathy, warmth, and understanding. Despite that excellent bedside manner, however, there is a fair argument that his medical talents were best exhibited in a research environment. For instance, he maintained that neither cholera, nor yellow fever, were contagious diseases, and opposed quarantine. These views became particularly unfortunate after he was appointed chief of the Advisory Committee on Public Hygiene in 1848. He also sometimes performed unnecessary operations on the sick toward some scientific end. This latter inclination was rendered even more problematic when coupled with the doctor's strong opposition to surgical anesthesia, believing it weakened the patient. But most would agree that Magendie's research contributions outweighed his limitations as a practicing physician. Indeed, the innovative physiologist himself grasped the confines in which physicians worked. He was quoted on the Who Named It Website as having said, "I hesitate not to declare, no matter how sorely I shall wound our vanity, that so gross is our ignorance of the real nature of the physiological disorders, called diseases, that it would perhaps be better to do nothing, and resign the complaint we are called upon to treat to the resources of nature, than to act (as) we are frequently compelled to do, without knowing the why and the wherefore of our conduct, and at obvious risk of hastening the end of the patient."

Contributed to the World of Science

Happily, Magendie's scientific research continued to yield impressive results long after his revelations of 1809. In 1813, he demonstrated the largely passive role of the stomach in vomiting and described the mechanism of swallowing as well. After serving on a commission to investigate the nutritional value of assorted food extracts in 1815, he continued to explore the field of nutrition and discovered such facts as mammals' reliance on protein to live and that not all proteins were equally life–sustaining. In 1817, Magendie published the first modern physiology textbook, A Summary of Physiology, in which he replaced theory with his revered facts. In 1821 he founded the Journal of Experimental Physiology, the first publication of its kind. In 1822, Magendie went on to publish the resultant findings of his experiments which he began in 1809 with his introduction of the effects and uses of such alkaloids as morphine, emetine, quinine, and strychnine. Around this same time he released his discoveries building on the 1811 work of Scottish anatomist Sir Charles Bell, in which he distinguished the motor and sensory functions of the spinal nerves, the anterior root being motor and the dorsal root sensory. What Bell had defined from anatomical evidence, Magendie verified in living animals. This was a seminal work in the field of physiology and became known as the Bell–Magendie Law.

Magendie made another important contribution in 1825, when he offered one of the first descriptions of cerebrospinal fluid. Among his other efforts were his groundbreaking observations of anaphylaxis (a kind of allergic reaction) and his description of a tiny opening in the brain (apertura medialis ventriculi quarte) that came to be known as the foramen of Magendie.

Magendie's astonishing body of work drew criticism, however, especially outside of France, for his use of live animals in his experiments. He was sometimes viewed as an extreme vivisectionist and characterized as seeing living organisms as simply complex machines that could be experimented upon without ethical consideration. On a visit to England in 1824, for instance, his public presentations of his experiments on the cranial nerves of living dogs caused a public outcry and a demand for the protection of animals. No matter how distasteful Magendie's methods may have been, however, they are difficult to judge in hindsight. There is nothing arduous, on the other hand, about appreciating the advances his research made possible.


Lasting Impact

As Magendie reached his 60s, he began to spend more and more time on his country estate (acquired through his 1830, and apparently happy, marriage to Henriette Bastienne de Puisaye) in Sannois. He retired from his duties at the Hotel–Dieu, where he started his career at 16, in 1845 and allowed his former student disciple, Bernard, to fill in for him at the College of France beginning in 1847. In his final years, Magendie remained busy conducting physiology experiments on plants. He died on October 7, 1855. Often referred to as the founder of experimental physiology, the fact–loving Magendie's additional outstanding contributions to such disciplines as pharmacology and nutrition rendered his impact on science unassailable.


Books

World of Biology, 2 volumes, Gale Group, 1999.


Online

"Bell–Magendie Law," Who Named It,http://www.whonamedit.com/synd.cfm/2383.html (January 9, 2005).

"Development of Experimental Pharmacology," General Anaesthesia, http://www.general-anaesthesia.com/magendie-pharmacology.htm (January 9, 2005).

"Dr. Francois Magendie (1783–1855)," BLTC,http://www.general-anaesthesia.com/images/francois-magendie.html (January 9, 2005).

"Dr. Francois Magendie (1783–1855)," Department of Neurology, University of Illinois at Chicago,http://www.uic.edu/depts/mcne/founders/page0057.html (January 9, 2005).

"Francois Magendie, Medicine, Biographies," AllRefer,http://reference.allrefer.com/encyclopedia/M/Magendie.html (January 9, 2005).

"Francois Magendie (1783–1855)," University of Virginia Health System, http://www.med.virginia.edu/hs-library/historical/classics/Magendiel.html (January 9, 2005).

"Francois Magendie," Who Named It?, http://www.whonamedit.com/doctor/cfm/2104.html (January 9, 2005).

"Magendie, Francois (1783 – 1855)," Science World,http://scienceworld.wolfram.com/biography/Magendie.html (January 9, 2005).

"Physiology," Microsoft Encarta Online Encyclopedia, http://encarta.msn.com/text–761577323–––1/Physiology.html (January 9, 2005).

"Sciencefare: September 25, 1986," Memorial University of Newfoundland, http://www.mun.ca/sgs/science/sept2586.html (January 9, 2005).

Magendie, François

views updated May 09 2018

Magendie, François (1783–1855) French physician; published the first modern physiology textbook Précis Élémentaire de Physiologie (1817), in which he demonstrated the importance of nitrogenous foods (protein) in the diet; in 1829 he stated that ‘all parts of the body of man undergo an intimate motion which serves to both expel those molecules that can or should no longer make up the body and replace them with new ones’—a concept rediscovered in 1942 by Schoenheimer as dynamic equilibrium.

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Francois Magendie

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