Kurt J. Varner, Ph.D. Laboratory
Pediatric Cardiology Fellow
Dhiraj Singh, MD
Research interests involve determining the mechanisms by which oxidative stress produces cardiac dysfunction. There are currently 2 major areas of research interest in my laboratory.
1) We are also studying the cardiovascular and cardiac toxicity produced by the inhalation of combustion-generated fine and ultrafine particulates. Our colleagues data show that these combustion generated particles may contain environmentally persistent free radicals (EPFR). Our studies are addressing the hypothesis that that these EPFRs produce cardiac toxicity by the combined actions of lung-derived systemic inflammation and localized oxidant and inflammatory actions at the level of the heart. 2) The second project involves the examination and characterization of the cardiac, cardiovascular, cardiovascular reflex and sympathetic nerve responses elicited by the acute and chronic administration of sympathomimetic stimulants. Biochemical, molecular biological and proteomic approaches are being used to identify the mechanisms underlying stimulant induced cardiac dysfunction.In addition, I am the director of the Cardiovascular Function Core Facility in the Department of Pharmacology at LSUHSC.
Lord, K., Moll, D., Lindsey, J.K., Mahne, S., Raman, G., Dugas, T., Cormier, S., Troxlair, D., Lomnicki, S., Dellinger, B and Varner, K.J. Environmentally persistent free radicals decrease cardiac function before and after ischemia/reperfusion injury in vivo. J. Receptor Sig. Trans. 31:157-167, 2011. PMC3152960.
Katz, PS, Trask, A.J., Souza-Smith, F.M., Hutchinson, K.P., Galantowicz, M., Lord, K.C., Stewart, J.A., Cismowski, M.J., Varner, K.J. and Lucchesi, P.A. Coronary arterioles in Type 2 diabetic (db/db) mice undergo a distinct pattern of remodeling associated with decreased vessel stiffness. Basic Res Cardiol. 106(6):1123-1134, 2011. PMC3229644.
Souza-Smith, F.M., Katz, P.S., Trask, A.J., Stewart, J.A. Jr, Lord, K.C., Varner, K.J., Vassallo,
D.V., Lucchesi, P.A. Mesenteric resistance arteries in type 2 diabetic db/db mice undergo outward remodeling. PLoS One. 6(8):e23337, 2011. PMC3150429.
Feng, Y., Hans C.P., McIlwain E., Seth D., Navar L.G., Varner K.J. and Lazartigues E. Angiotensin-converting enzyme 2 over expression in the central nervous system reduces angiotensin-II-mediated-cardiac hypertrophy. PLoS One, 7(11) e48910, 2012. PMC3498357
Mahne, S., Chuang, G.C., Pankey, E., Kiruri, L., Kadowitz, P.J., Dellinger, B. and Varner, K.J. Environmentally persistent free radicals decrease cardiac function and increase pulmonary artery pressure. Am. J. Physiol. Heart and Circ. Phys. 303: H1135-1142, 2012. PMC3517644.
Varner, K.J., Daigle, K., Weed, P.F., Lewis, P.B., Mahne, S.E., Sankaranarayanan, A. and Winsauer, P.J. Comparison of the behavioral and cardiovascular effects of mephedrone with other drugs of abuse in rats. Psychopharm 225:675-685, 2012. PMC3538107.
Kelly, M., Hebert, V., Thibeaux, T., Orchard, M., Hasan, F., Cormier, S., Thevenot, P., Lomnicki, S., Varner, K., Dellinger, B., Dugas, T. Model Combustion-generated particulate matter containing persistent free radicals redox cycle to produce reactive oxygen species. Chem Res Tox, in press 2013.
Cardiovascular Function Core
Dr. Varner is also the director of the Cardiovascular Function Core Facility in the Department of Pharmacology. This core facility is funded in part by the COBRE grant (P20-RR018766) awarded to Daniel Kapusta, Ph.D. and Patrice Delafontaine, MD. This core facility was established to provide in vivo models to study cardiovascular function. The following techniques are routinely used in our facility.
- Radio telemetric monitoring of arterial pressure, heart rate and ECG
- Ultrasonic imaging and analysis
- Analysis of left ventricular function in vivo using Millar pressure-volume catheters
- Sympathetic nerve recording
- Acute cardiovascular recording
- Analysis of heart rate variability
- Complete pulmonary function