Basement membrane and interstitial matrices in the regression of the male rat paramesonephric duct: L.J. Pelliniemi (1), J. Paranko (2) and J-M. Foidart (3). Laboratory of Electron Microscopy (1) and Department of Anatomy (2), University of Turku, SF-20520 Turku, Finland, and Clinic of Gynecology and Obstetrics (3), University of Liège, B-4020 Liège, Belgium