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Willis K. Samson, Ph.D., D.Sc.

Pharmacological and Physiological Science

Graduate Programs in the Biomedical Sciences


Ph.D. (Physiology) University of Texas Southwestern Medical Center, 1979
Postdoc U. TX Southwestern, 1979-1981

Previous Positions

1981-1988 Assistant Professor (Physiol) U TX Southwestern Medical Center
1988–1990 Associate Professor (Anat/Neurobiol) U MO-Columbia Med School
1990-1992 Professor (Anat/Neurobiol) U MO-Columbia Medical School
1992-1999 Professor and Chairman (Physiol) U ND Medical School
1997–1998 Professor and Chairman (Pharmacol/Toxicol) UND Medical School
1999–present Professor (Pharm/Phys Science), Director of Graduate Programs in the Biomedical Sciences Saint Louis University


We study the roles played by vasoactive peptides in the co-ordinated regulation of cardiovascular homeostasis. Cardiovascular homeostasis (health) is maintained by hormonal and neuronal mechanisms all integrated to assure adequate cardiac function. This requires communication among numerous tissues (e.g. blood vessels, kidneys, adrenal glands, brain and the heart itself) and it has become clear that these organ systems are not only interconnected via nerves, but also that a blood borne system of messengers (i.e. hormones) acts to also co-ordinate their function. These hormones are actually small proteins that are produced in many tissues, most notably the blood vessels themselves, the heart and even the brain where they function as neurotransmitters.

Our particular focus is how these vasoactive peptides act in brain (as neurotransmitters) and in the anterior pituitary gland (controlling the release of classical hormones) so that cardiovascular and renal function is maintained. In particular we are interested in how our bodies regulate fluid and electrolyte intake and excretion. Volume status and plasma osmolality are factors that can seriously compromise cardiac function. We study how these small peptides act in brain to control salt and water intake and how they modify autonomic nervous system function (which then controls blood pressure). Currently we are studying the actions of three classes of peptides in brain and pituitary gland: the adrenomedullins, the hypocretins/orexins, and the recently described prolactin releasing peptides. What these peptides have in common is the ability to alter cardiac performance by actions in brain. We study those actions of these peptides in vivo and in tissue culture system in vitro, employing both classical pharmacologic approaches and more modern molecular technologies. Our long term goals are to understand the relevance of the actions of these peptides in brain and to establish the potential for their use in clinical settings.

Labs and Facilities

Recent Graduates

Alison Salvatori, Ph.D., 2008
Project: Novel Pancreatic Islet Peptides

Gina L.C. Yosten, Ph.D., 2010
Project: Central Autonomic and Metabolic Actions of Neuronostatin

Alicia Pate, Ph.D., 2012
Project: Prolactin ReleasingPeptides and Stress

Molly Elrick, Ph.D., 2014
Project: Ligands for Orphan Receptors

Chloe Bryant, Ph.D., 2014
Project: Novel Neuroendocrine Peptides and Reproductive Function

Current Graduate Students

Lauren Stein
Project: Orphan G Protein-Coupled Receptor Identification


Samson W K, JV Zhang, Avsian-Kretchmer O, Cui K, Yosten GLC, Klein C, Lyu Rm, Wang YX, Chen XQ, Yang J, Price CJ, Hoyda TD, Ferguson AV, Yuan XB, Chang JK, Hsueh AJW 2008 Neuronostatin encoded by the somatostatin gene regulates neuronal, cardiovascular, and metabolic functions. Journal of Biological Chemistry 283(46): 31949-59 PMCID: PMC2581552

Hua Y, H Ma, WK Samson, J Ren 2009 Neuronostatin inhibits cardiac contractile function via a protein kinase A- and JNK-dependent mechanism in murine hearts. American Journal of Physiology 297: R682-R689. PMCID: PMC2739787

Yosten GLC, Samson WK 2010 The melanocortins, not oxytocin, mediate the anorexigenic and antidipsogenic effects of neuronostatin. Peptides 31:1711-1714. PMCID: PMC2935629

Yosten GLC, Pate AT, Samson WK 2011 Neuronostatin acts in brain to biphasically increase mean arterial pressure via sympatho-activation followed by vasopressin secretion: the role of melanocortin receptors. American Journal of Physiology 300: R1194-R1199. PMCID: PMC3094032

Yosten GLC, Redlinger L, Samson WK 2012 Evidence for a role of endogenous nesfatin-1 in the control of water drinking. Journal of Neuroendocrinology 24: 1078-1084. PMID: 22375892

Yosten GLC, Samson WK 2012 Pressor doses of vasopressin result in only transient elevations in plasma peptide levels. Peptides 33:342-345. PMID: 22227112

Yosten GLC, Redlinger LJ, Samson WK 2012 Evidence for an interaction of neuronostatin with an orphan G protein-coupled receptor, GPR107. American Journal of Physiology 303: R941-R949. PMCID: PMC 3517703

Yosten GLC, Lyu RM, Hsueh AJW, Avsian-Kretchmer O, Chang JK, Bryant CW, Dun SL, Dun N, Samson WK 2013 A novel reproductive hormone, phoenixin. Journal of Neuroendocrinology, 25: 206-215, 2013. PMID: 22963497

Pate AT, Yosten GLC, Samson WK 2013 Neuropeptide W increases mean arterial pressure as a result of behavioral arousal. American Journal of Physiology 305: R804-R810. PMID: 23926134

Pate AT, Yosten GLC, Samson WK 2013 Compromise of endogenous neuropeptide W production abrogates the dipsogenic and pressor effects of angiotensin II in adult, male rats. Journal of Neuroendocrinology 25: 1290-1297. PMID: 24628220

Yosten GLC, Kolar GR, Redlinger LJ, Samson WK 2013 Evidence for an interaction between pro-insulin C-peptide and GPR146. Journal of Endocrinology 218: B1-B8. PMID: 23980258.

Salvatori AS, Elrick MM, Samson WK, Corbett JA, Yosten GLC 2014 Neuronostatin inhibits glucose-stimulated insulin secretion via direct action on the pancreatic alpha cell. American Journal of Physiology 306: E1257-E1263. PMID: 24735891

Liu J, Yosten GLC, Ji H, Zhang D, Zheng W, Speth RC, Samson WK, Sandberg K 2014 Selective inhibition of angiotensin receptor signaling through Erk1/2 pathway by a novel peptide. American Journal of Physiology 306: R619-R626. PMID: 24523339

Yosten GLC, Samson WK 2014 Neural circuitry underlying the central hypertensive action of nesfatin-1: melanocortins, corticotropin releasing hormone, and oxytocin. American Journal of Physiology 306: R722-R727. PMID: 24598461


NIH R001 HL121456-01A1, "Angiotensin Receptor Regulation by Upstream Short Open Reading Frames." July 1, 2014 - June 30, 2019

Honors and Awards


1967 Rufus Choate Leadership Award, Duke University


1977 Sigma Xi Student Research Award, University of Texas Health Science Center at Dallas

1978 Sigma Xi Student Research Award, University of Texas Health Science Center at Dallas


1995 Portrait Award (Outstanding Faculty Award, selected by Medical Students), University of North Dakota School of Medicine

1999 Elected Fellow of the American Heart Association (High Blood Pressure Council)

2010 Doctor of Science (Hon.), Westminster College, Fulton, MO

2012 Distinguished Teacher Award (Saint Louis University School of Medicine, M.D. Program)

Professional Organizations and Associations

Professional Societies

Endocrine Society (Chairman, Public Communications Committee, 1994-1996;

Member, Development Committee 2002-2005)

American Physiological Society (Member, Public Affairs Committee 1999-2003, Member, Joint Program Steering Committee, Section on Endocrinology and Metabolism, 2005-2012)

International Society for Neuroendocrinology

Association of Chairman of Departments of Physiology (1992-1999)

American Heart Association, High Blood Pressure Research Council (Fellow)

Editorial Boards

American Journal of Physiology: Regulatory, Integrative, and Comparative Physiology (Associate Editor and Deputy Editor-in-Chief, 2007- 2013, Editor-in-Chief 2013-2019)
Endocrinology (Member, Editorial Board, 1986-1989 and 1994-1997)
Trends in Endocrinology and Metabolism (Member, Editorial Board, 2000-2009; Editor, Research News in Endocrinology and Metabolism, 2000-2008)
Endocrine News (Editor in Chief, 1994-1998)
Endocrine (Member, Editorial Board, 1994-2010)
Regulatory Peptides (Member, Editorial Board, 2001-2010)
Peptides (Member, Editorial Board, 2005-2010)
Endocrine (Guest Editor, Special Issue on Prolactin, 2003)
Regulatory Peptides (Guest Editor, Special Issue on Adrenomedullin, 2003)
Immunology, Endocrine and Metabolic Agents in Medicinal Chemistry (Guest Editor, Special Issue on Appetite, 2008)