Wolffian Duct>>?
• Changes the surrounding duct cells to express
Pax-2.
• Pax-2 is required for all subsequent steps.
• As the Wolffian duct advances caudally,
nephrons appear on either side of the duct. The
nephrons form perpendicular to the cord. The
are called ‘mesonephric tubules’. 20-30 tubules
form. It is functional in amphibia and fish, but in
mammals only the cranial 4-6 attach to the
Wolffian duct, and the rest will degenerate.