Dr. Pisegna’s main research interest is the molecular pharmacology of hormones and receptors in the gastrointestinal tract. These research and clinical interests derive from research in the biochemistry and molecular physiology of neuroendocrine tumors as well as an understanding of the molecular interaction of peptide hormones and their receptors. His clinical efforts are currently focused on the management of gastric hypersecretory conditions, neuroendocrine tumors of the GI tract, and Zollinger Ellison Syndrome (ZES), medical conditions that derive from alterations in the expression of gastrointestinal hormones. Dr. Pisegna cloned the receptor for human cholecystokinin A (CCKA), the cholecystokinin B (CCKB or gastrin) receptor and the pituitary adenylate cyclase activating polypeptide (PACAP) receptor. He has previously demonstrated that PACAP is a potent stimulant of gastric acid secretion and is expressed on neurons innervating the stomach, on enterochromaffin-like cells (ECL) of the stomach expressing receptors for PACAP. Using mice lacking the PAC1 receptor, he has demonstrated that the mice develop a gastric acid hypersecretory condition resulting from hypergastrinemia.Recently his lab is focused on understanding the role of peptide hormones in the development of obesity, metabolic syndrome and NAFLD. Dr. Pisegna's research interests extend to understanding the molecular mechanisms involved in satiety and metabolic syndrome including the role of the gastrointestinal microbiome.
UCLAProfessor,Vatche and Tamar Manoukian Division of Digestive DiseasesMember,I3T ThemeMember,Molecular, Cellular & Integrative Physiology GPB Home Area
M.D., University of Miami School of Medicine, 1986