Friedrich Gustav Jacob Henle (1809-1885), German anatomist. Henle's work on cell epithelia, while a student of Johannes Muller, prepared the way for the study of cytology. His studies took him to Paris, where after graduating he went into politics. The post-Napoleonic war years were unsettled times and he was imprisoned for six years, but served only a few weeks before being pardoned. Taking a post at the university of Berlin and then Zurich, he began his extensive study of anatomy, publishing his Handbook of Rational Pathology in 1853. Henle is best known for the loop within the kidneys that bears his name, which he first observed in 1862.