ROLE OF PITUITARY ADENYLATE CYCLASE-ACTIVATING POLYPEPTIDE (PACAP) IN THE BED NUCLEUS OF THE STRIA TERMINALIS (BNST): INVOLVEMENT IN STRESS AND ANXIETY A Thesis Presented by Joseph Cheung to The Faculty of the Graduate College of The University of Vermont In Partial Fulfillment of the Requirements for the Degree of Master of Science Specializing in Neuroscience April 17th, 2009