INTRODUCTION TO THE BILIARY-TRACT, THE GALLBLADDER, AND GALLSTONES

This paper serves to introduce a topical section of fifteen invited or iginal research contributions dealing with normal and pathological dev elopment of the human biliary tract. This section also includes compar ative anatomy of the gallbladder and the cystic duct as well as, the f ormation of gallstone. This series of reports have used advanced micro scopic and ancillary techniques to study adaptative changes in gallbla dder epithelial cell changes regarding permeability, renewal, mucous s ecretion as well as cholesterol uptake and nucleation. Several contrib utions deal with the blood and lymphatic drainage of the gallbladder. The gallbladder contractility is clarified by recent findings about it s innervation, elegantly demonstrated and supported by complementary i mmunohistochemical and neurophysiological techniques. In vivo models f or production of cholelithiasis in the ground squirrel and the Syrian hamster are introduced. Recent in vitro cellular and molecular models have substantially increased the understanding of biliary tract calcul i formation. Finally, a survey and new data about progesterone gene re gulation of both cholesterol metabolism and gallstone formation obtain ed in the Syrian hamster model are compared with cholelithogenesis in human. (C) 1997 Wiley-Liss, Inc.