Mark W. Chapleau, Ph.D.

Professor of Medicine and
Molecular Physiology & Biophysics

Physiology, Louisiana State University Medical Center

Research Interests

My research program focuses on discovering the molecular and cellular mechanisms that determine baroreceptor reflex sensitivity in normal and pathological states. The roles of specific mechanosensitive, voltage-gated, and ligand-modulated ion channels on baroreceptor afferent and sympathetic efferent neurons are investigated. Projects funded by the Dept. of Veterans Affairs and NIH address interactions between chronic hypertension, atherosclerosis, and aging that contribute to impaired baroreflex sensitivity and autonomic dysfunction. Integrated neuro-cardiovascular function, including recordings of baroreceptor afferent activity and renal sympathetic nerve activity in vivo, is assessed in genetically-modified mice. Ion channel properties and cellular mechanisms are explored in studies of isolated baroreceptor and sympathetic neurons maintained in culture. Along with other methods, adenoviral-mediated gene transfer is used to reveal molecular mechanisms and determine the influence of changes in gene expression on baroreflex function. Angiotensin and reactive oxygen species are proposed as key mediators of baroreflex dysregulation in atherosclerosis, hypertension, and aging.

Selected Publications

Ma, X., Sigmund, C.D., Hingtgen, S.D., Tian, X., Davisson, R.L., Abboud, F.M., and Chapleau, M.W.: Ganglionic Action of Angiotensin Contributes to Sympathetic Activity in Renin-Angiotensinogen Transgenic Mice. Hypertension 2[part 2]: 312-316, 2004.

Ma, X., Zhang, H.J., Whiteis, C.A., Tian, X., Davisson, R.L., Kregel, K.C., Abboud, F.M., and Chapleau, M.W.: NAD(P)H Oxidase-induced Oxidative Stress in Sympathetic Ganglia of Apolipoprotein E Deficient Mice. Auton Neurosci 126-127(1-2): 285-291, 2006.

Ma, X., Bielefeldt, K., Tan, Z.Y., Whiteis, C.A., Snitsarev, V., Abboud, F.M., and Chapleau, M.W.: Dual Mechanisms of Angiotensin-induced Activation of Mouse Sympathetic Neurones. J. Physiol. 573.1: 45-63, 2006.

Snitsarev, V., Whiteis, C.A., Chapleau, M.W., and Abboud, F.M.: Mechano- and Chemo-Sensitivity of Rat Nodose Neurones - Selective Excitatory Effects of Prostacyclin. J. Physiol., 582.1: 177-194, 2007.