Claude Bernard on Experimental Medicine—Some Unpublished Notes

CLAUDE BERNARD ON EXPERIMENTAL MEDICINESOME UNPUBLISHED NOTES HEBBEL E. HOFF, ROGER GUILLEMIN, and EDVART SAKlZ* One hundred years ago Claude Bernard was at the pinnacle ofhis scientific productivity andhis inteEectual powers, ifnot ofhis reputation. Some thirty years earlier he arrived in Paris at the age of twenty-one with the manuscript ofa not-too-original play in his pocket and an unsatisfactory and incompleted apprenticeship in pharmacy behind him. He enrolled in the Faculty ofMedicine. There he came under the influence ofMagendie and, gaining his internship in 1839, became Magendie's preparator in 1841. In 1843, at the age ofthirty, he obtained the medical degree and completed his first work on the metabolism ofsugar, concluding that sucrose is modified in digestion by demonstrating its presence in the bloodstream only when it was injected intravenously and never when it was ingested. This was followed during the next fifteen years by studies on the function of the pancreas in the digestion of fat, on the metabolism of starvation, on the glycogenic function ofthe liver and the sugar piqûre, on the localization ofthe action ofcurare, and on the vasomotor nerves. In a very early investigation he measured the temperature of the blood in the right and left ventricles ofthe horse and showed that the blood of the right cavity was warmer than that in the left, disposing thereby of the suggestion of Lavoisier that bodily oxidations take place in the lungs. In so doing he had recourse to catheterization ofthe cardiac chambers, and, although he was not the first to do so, his report of this procedure had much to do with initiating the chain ofevents that led from Chauveau and Marey to Forssmann and Cournand. Few physiologists could rival such an output and even fewer its versatility and quality. Johannes Müller and Magendie, the founders ofthe new * Department ofPhysiology, Baylor University College ofMedicine, Houston, Texas. This work was supported in part by USPH GM-06518-03A1. The text is based on a review of Bernard's Introduction to the Study ofExperimental Medicine that appeared in the Bulletin ofthe History ofMedicine, 36:177, 1962. 30 Hebbel E. Hoff et al. · Claude Bernard on Experimental Medicine Perspectives in Biology and Medicine · Autumn 1964 physiology were dead—Magendie in 1855 and Müller in 1858. Helmholtz, eight years younger than Bernard, was called to the chair ofphysiology at Heidelberg in 1858; his studies on the conservation ofenergy, on the ophthalmoscope, the physiology ofvision and audition, and the velocity ofthenerve impulsewerebehind him, and his great work on wave mathematics ahead. DuBois-Raymond, who took up his chair at Berlin in 1858, was clearly the doyen of electrophysiology. Virchow's Cellular Pathology was published in 1858. Flourens, the French neurophysiologist whom we remember for his studies on the respiratory center and the cerebellum, was in his middle sixties and largely occupied by his duties as permanent secretary of the French Academy of Sciences and as a member of the august French Academy. Pasteur was then celebrated as the outstanding chemist of France; his studies on fermentation and spontaneous generation were coming to a climax and those on the spoiling ofwine and the pébrine were just over the horizon. Bernard's physical forces were, however, sadly depleted. In i860 he had been stricken with an obscure chronic intestinal illness which must have been some form of enteritis or colitis. Whatever it was and whatever its cause, it enforced a physical idleness of over two years, which Bernard spent at his parental property in the Beaujolais, where each year he went to supervise the harvest ofthe grapes and the vintage. It was during these years of absence from the laboratory that Bernard wrote the classical Introduction to the Study ofExperimental Medicine as the beginning ofa more lengthy volume on experimental medicine that was never written. Using notes collected over the years—and in particular after 1850 in a small notebook bound in red cardboard, the famous Cahier Rouge—Bernard set forth what appeared to him to be the fundamental ground rules of the experimental approach to physiology and medicine. It is from the translation ofthis work recently republished (Dover Publications, 1957) that all the following quotations...