Aim of this volume is to clarify the relationship between molecular structure and function of tight junction proteins, as well as their regulation and their role in diseases. Current research may form a basis for future diagnostic and therapeutic approaches to diseases which seem to have not much in common but are characterized by defects of organ barriers, like Crohn's disease, renal hypertension, inner ear deafness, and cancerous diseases. Topics include the functions of distinct tight junction proteins as barrier or channel formers for solutes and water, characteristics of the tight junction in inflammatory bowel diseases, posttranslational modifications of tight junction proteins, the relation between renal tight junction proteins and blood pressure control, and the molecular structure of claudin-claudin interactions-Note: Annals volumes are available for sale as individual books or as a journal. For information on institutional journal subscriptions, please visit www.blackwellpublishing.com/nyas. ACADEMY MEMBERS: Please contact the New York Academy of Sciences directly to place your order (www.nyas.org). Members of the New York Academy of Science receive full-text access to the Annals online and discounts on print volumes. Please visit http://www.nyas.org/MemberCenter/Join.aspx for more information about becoming a member.