Research Interests:
Research in my laboratory is directed towards gaining an integrative
understanding of the role of the central nervous system in the long-term
regulation of arterial pressure and the pathogenesis of hypertension. At
the present time we are investigating how circulating hormones, such as
angiotensin II and aldosterone, are monitored by specialized sites within
the brain called circumventricular organs. We are investigating how these
regions influence ongoing sympathetic nerve discharge and ultimately the
regulation of arterial pressure. Our long-term goal is to understand, in a
quantitative way, the role of such hormonal-sympathetic interactions in
normal physiology and the pathophysiology of hypertension. Specifically, we
are studying how such interactions are influenced by alterations in dietary
salt in hopes of understanding the neurogenic basis of salt-dependent
hypertension. A variety of experimental approaches are employed to address
these issues including state-of-the-art long-term monitoring of
cardiovascular hemodynamics and direct measurement of sympathetic nerve
discharge in awake animals. We have also initiated a collaborative project
with the Department of Mathematics to begin developing new mathematical
models of how the nervous system regulates cardiovascular function over
long periods of time.
In addition to the work in my own laboratory, I am the coordinator for a
newly formed national research effort to study the role of the brain in
cardiovascular diseases. "The Neurogenic Cardiovascular Diseases
Consortium" is a novel NIH funded project which joins 5 major research
Universities to investigate neurogenic cardiovascular diseases at all
levels of regulation; gene, single cell, neural networks and whole animal.
This work will be carried out by Universities of Minnesota (home
institution), Pittsburgh, Texas-San Antonio, Florida-Gainesville and
Michigan State University.
Selected Publications:
(For a comprehensive list of recent publications, refer to PubMed, a service provided by the National Library of Medicine.)
Abrams, J. and J. W. Osborn. Role of benzamil blockable sodium channels in
the brain in salt-sensitive hypertension. Clin. Exp. Physiol. Pharm.
35(5-6):687-694, 2008.
Yoshimoto, M., E.A. Wehrwein, M. Novotny, G. M. Swain, D. L. Kreulen and J.
W. Osborn. Effect of stellate ganlionectomy on basal cardiovascular
function and responses to chronic b1 adrenoceptor blockade in the rat. Am
J. Physiol. H2447-H2454, 2008.
Osborn JW, Collister JP, Guzman P. Effect of peripheral sympathetic nerve dysfunction on salt sensitivity of arterial pressure. Clin Exp Pharmacol Physiol. 2007 Oct 30.
McBryde FD, Guild SJ, Barrett CJ, Osborn JW, Malpas SC. Angiotensin II-based hypertension and the sympathetic nervous system: the role of dose and increased dietary salt in rabbits.
Exp Physiol. 2007 Sep;92(5):831-40.
King AJ, Osborn JW, Fink GD. Splanchnic circulation is a critical neural target in angiotensin II salt hypertension in rats. Hypertension. 2007 Sep;50(3):547-56.
Osborn JW, Fink GD, Sved AF, Toney GM, Raizada MK. Circulating angiotensin II and dietary salt: converging signals for neurogenic hypertension. Curr Hypertens Rep. 2007 Jun;9(3):228-35. Review.
Osborn JW, Jacob F, Hendel M, Collister JP, Clark L, Guzman PA. Effect of subfornical organ lesion on the development of mineralocorticoid-salt hypertension. Brain Res. 2006 Sep 13;1109(1):74-82.
Collister JP, Osborn JW. Role of a responsive sympathetic nervous system in the chronic hypotensive effects of losartan in normal rats. J Cardiovasc Pharmacol. 2005 Aug;46(2):147-54.
Jacob F, Clark LA, Guzman PA, Osborn JW. Role of renal nerves in development of hypertension in DOCA-salt model in rats: a telemetric approach. Am J Physiol Heart Circ Physiol. 2005 Oct;289(4):H1519-29.
Osborn JW. Hypothesis: set-points and long-term control of arterial pressure. A theoretical argument for a long-term arterial pressure control system in the brain rather than the kidney. Clin Exp Pharmacol Physiol. 2005 May-Jun;32(5-6):384-93.
Jacob F, LaBine BG, Ariza P, Katz SA, Osborn JW. Renal denervation causes chronic hypotension in rats: role of beta1-adrenoceptor activity. Clin Exp Pharmacol Physiol. 2005 Apr;32(4):255-62.
Osborn JW, Jacob F, Guzman P. A neural set point for the long-term control of arterial pressure: beyond the arterial baroreceptor reflex. Am J Physiol Regul Integr Comp Physiol. 2005 Apr;288(4):R846-55.
Recent Graduate Students
Joanna Abrams (Ph.D. 2008, Neuroscience, University of Minnesota).
John P. Collister, D.V.M, Ph.D. 1999. Graduate program in Molecular
Veterinary Biosciences. Dissertation: "Angiotensin-sympathetic interactions
in the long-term control of arterial pressure". Current Position:
Research Associate, Department of Veterinary PathoBiology, University
of Minnesota.
David P. Slovut, M.D., Ph.D. 1998. Graduate Program in Cellular
and Integrative Physiology. Dissertation: "Mechanisms of heart rate
variablity after cardiac allograft transplantation. Current Position:
Cardiology Fellow, University of Michigan.
Scott Carlson, Ph.D. 1996. Graduate Program in Cellular and Integrative
Physiology. Dissertation: "The role of peripheral osmoreceptors
in the control of arginine vasopressin release". Current Position:
Assistant Professor, Luther College.
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