Development, Differentiation and Derivatives of the Wolffian and Müllerian Ducts

The Wolffian ducts (proand mesonephric ducts) are the most important and earliest structures formed during the development of the urogenital system in vertebrates including humans. The Wolffian ducts originate in the prospective cervical region of the young embryo but later migrate caudally inducing the development of the pronephric and mesonephric tubules along their migratory route. In addition to being the inducers of the first two generations of the kidney, namely the pronephros and mesonephros, the Wolffian ducts also give rise to the ureteric buds which drive the growth and differentiation of the permanent kidneys, the metanephroi. The paired ureteric bud arises as outpouching from the caudal end of the Wolffian duct and induces the epithelialisation of the metanephric blastema leading to the formation of the renal corpuscles and tubular part of the nascent metanephric kidney, while the entire collecting system consisting of the ureter, the renal pelvis, the calyces and the collecting ducts take their origin from the ureteric bud.