Rudolf Heidenhain

Rudolf Peter Heinrich Heidenhain (1834 to 1897) was a German physiologist born in Marienwerder in the Province of Prussia, now Kwidzyn in Poland. He studied medicine at the universities of Halle and Berlin, assisted Emil du Bois-Reymond in Berlin and later worked in the Halle laboratory of Alfred Wilhelm Volkmann. In 1859 he took the chair of physiology at the University of Breslau, where he stayed for the rest of his career and taught students who included Ivan Pavlov. He is remembered for work on muscle and nerve physiology, showing that a muscle releases more energy under a heavier load and works more economically when fatigued, and for measuring the small rise in temperature that follows even slight movement. He also studied the secretion and absorption processes of glands, including the gastric glands that make pepsin and hydrochloric acid, and the half-moon cell structures of the salivary glands named the demilunes of Heidenhain. His son Martin Heidenhain became a respected anatomist.