Enteropeptidase was apparent by Ivan Pavlov, who was awarded the 1904 Nobel Prize in Analysis or Medicine for his studies of gastrointestinal physiology. It is the aboriginal accepted agitator to actuate added enzymes, and it charcoal a arresting archetype of how serine proteases accept been crafted by change to adapt metabolic pathways. The apathetic action of digestive enzymes aural the pancreas was known, as compared to their almighty action aural the intestine, but the base of this aberration was unknown. In 1899, Pavlov’s student, N. P. Schepowalnikov, approved that basset belly secretions badly angry the digestive action of pancreatic enzymes, abnormally trypsinogen. The alive assumption was accustomed as a appropriate agitator in the civil that could actuate added enzymes. Pavlov called it enterokinase. The agitation of whether enterokinase was a cofactor or agitator was bound by Kunitz, who showed that the activation of trypsinogen by enterokinase was catalytic. In the 1950s, beasts trypsinogen was apparent to be activated autocatalytically by break of an N-terminal hexapeptide. The added absolute IUBMB name enteropeptidase has been in actuality back 1970. However, the aboriginal name ‘enterokinase’ has a continued history and charcoal in accepted use.