First steps in Claude Bernard's discovery of the glycogenic function of the liver

Unwarranted assumptions: Claude Bernard and the growth of the vera causa standard

“…Notice that Bernard often referred to his own comparative experiments as furnishing counterproofs (Bernard 1949, e.g., 153, 156, 164). 33 This eventually led to the discovery of the process of hepatic glycogenesis, and it has been studied in depth on the basis of extant laboratory notebooks (Grmek 1968, Holmes 1974. While Bernard's summary in the Introduction condenses and rearranges the chronology of the process of discovery, it appears to describe the role of the counterproof accurately.…”

Brain Glycogen Structure and Its Associated Proteins: Past, Present and Future

“…It is not surprising that the fundamental study of its structure and metabolism began in liver and muscle. Claude Bernard, through a series of fundamental experiments, discovered the primary role of the liver in supplying glucose to other organs through the bloodstream (reviewed by Young 1937Young , 1957Grmek 1968). In 1848, Bernard noticed that after death, a large amount of glucose was released from the hepatic veins of a dog, even when the dog had not been fed any carbohydrates (Grmek 1968).…”

“…Claude Bernard, through a series of fundamental experiments, discovered the primary role of the liver in supplying glucose to other organs through the bloodstream (reviewed by Young 1937Young , 1957Grmek 1968). In 1848, Bernard noticed that after death, a large amount of glucose was released from the hepatic veins of a dog, even when the dog had not been fed any carbohydrates (Grmek 1968). He concluded that the liver could produce glucose, and by 1857, reported that he could extract glycogen (a term that literally means "sugar-former") by plunging the tissue in boiling water shortly after death and precipitating the material with alcohol (Bernard 1857) (Fig.…”

Laboratory Notebooks and Investigative Pathways

“…Quite naturally, Grmek inferred that this was the experiment to which Bernard referred in the story he afterward told, and accepted Bernard's account of its immediate consequence: that "Claude Bernard was immediately led to see that the old theory about the nutritive origin of animal sugar was false, and that the liver produced sugar." 2 In my interpretation of this experiment I differed somewhat from Grmek. Having found other evidence that Bernard had long been skeptical of theories derived from chemical reasoning alone, as was this "reigning" theory of nutrition, I argued that Bernard's surprise was not focused on the general presence of sugar in the blood of an animal that had eaten no sugar for eight days, but on its specific presence in the portal vein.…”