Claude Bernard and his revelations in physiology

Abstract

It was in Saint-Julien near Villefranche that Claude Bernard was born on 12 July 1813. About 20 years later he moved to Paris to become a dramatist but was directed into the study of medicine, the service at the Hôtel Dieu of Magendie that led him to the Collège de France. He entered Magendie's laboratory as a voluntary assistant and within a year became official préparateur. His early work on the chorda tympani and his MD thesis on gastric juice in 1843 set him on his lifelong discoveries in physiology. The central role of hepatic glycogenesis in the formation of sugar in animals was established around 1850, and he proceeded to show that section of the cervical fibres of the sympathetic chain led to congestion and increased temperature on that side of the face-resulting from paralysis of the vasomotor nerves. And there were vasodilator as well as vasoconstrictor fibres. After the salivary glands, the pancreas caught his attention and he discovered its ability to emulsify fatty material. Toxic and therapeutic substances were analysed: carbon monoxide paralyses carriage of oxygen by taking its place on haemoglobin; and curare abolishes voluntary movement by paralysis at the motor end-plate. But Bernard was above all a general physiologist, exemplified in 1872 and 1873 in his Lectures on the phenomena of life common to animals and plants, summarised in the aperçu 'the constancy of the internal environment is the condition of the free and independent life'. Claude Bernard died on Sunday 10 February 1878 in Paris.