Research Interest:

I have two main research interests. I. How natiuretic peptides and nitric oxide and their second messenger cyclic GMP serve as a "brake" on myocardial function and how this changes in disease. II. The relationship between excitatory and inhibitory amino acid receptors and cerebral oxygen consumption and how their role changes in disease.

Description:

In the heart, we are currently exploring the relationship between signal transduction and the control of local metabolism. We are focusing on the natriuretic peptide nitric oxide-cyclic GMP signal transduction system, which acts as a "brake" on myocardial function. This system exerts significant control of oxygen supply/consumption through direct effects on myocytes and vascular smooth muscle. We are attempting to determine the mechanisms through which this system operates and how problems like myocardial infarction and heart failure affect the responses to this system. For example, in failure, the activity of this system is increased but its effects are greatly reduced. We would like to correct this problem.

In the brain, excitatory amino acids, such as glutamate, increase cerebral oxygen consumption, while other amino acids reduced consumption. The relative importance of the various receptors in the control of cerebral metabolism is not known. Activation of these receptors also affects cerebral blood flow. How the relationship between cerebral oxygen supply and consumption is affected by these receptors is not known. We also wish to determine the importance of the various receptor subtypes in the control of cerebral metabolism during stroke and autism.

Publications:

Chi, O.Z., C. Hunter, X. Liu, T. Tan and H.R. Weiss.  Effects of VEGF on blood-brain barrier disruption caused by hyperosmolarity.  Pharmacol. (in press).

Luciano, J.A., T. Tan, Q. Zhang, E. Huang, P.M. Scholz and H.R. Weiss.  Hypoxia inducible factor-1 improves the action of nitric oxide and natriuretic peptides after simulated ischemia-reperfusion.  Cell. Physiol. Biochem. (in press).

Weiss, H.R., X. Liu and O.Z. Chi.  Cerebral O 2 consumption in young Eker rats: effects of GABA blockade: implications for autism. Intern. J. Develop. Neurosci. (in press).

Chi, O.Z., C. Hunter, X. Liu and H.R. Weiss.  Effects of erythropoietin on blood-brain barrier disruption in focal cerebral ischemia.  Pharmacol. 82:38-42, 2008.

Chi, O.Z., C. Hunter, X. Liu and H.R. Weiss.  Effects of deferoxamine on blood brain barrier disruption and VEGF in focal cerebral ischemia.  Neurol. Res. 30:288-293, 2008.

Weiss, H.R., X. Liu, Q. Zhang and O.Z. Chi.  Increased cerebral O 2 consumption in Eker rats and effects of N-methyl-D aspartate blockade: implications for autism.  J. Neurosci. Res. 85:2512-2517, 2007.

Anyadike, C., P.M. Scholz, Q. Zhang, E. Katz and H.R. Weiss.  Brain natriuretic peptide reverses the effects of myocardial stunning in rabbit myocardium.  Pharmacol. 80:40-48, 2007.

Zhang, Q., P.M. Scholz, A. Pilzak, J. Su and H.R. Weiss.  Role of phospholamban in cyclic GMP mediated signaling in cardiac myocytes.  Cell Physiol. Biochem. 20:157-166, 2007.

Tan, T., Q. Zhang, C. Anyadike, P.M. Scholz and H.R. Weiss. Chronic nitrates blunt the effects of not only nitric oxide but also natriuretic peptides in cardiac myocytes. Pharmacol. Res. 56:49-55, 2007.

Chi, O.Z., C. Hunter, X. Liu and H.R. Weiss. Effects of anti-VEGF antibody on blood-brain barrier disruption in focal cerebral ischemia. Exp. Neurol. 204:283-287, 2007.

Zhang, Q., P.M. Scholz, A. Pilzak, J. Su and H.R. Weiss. Role of phospholamban in cyclic GMP mediated signaling in cardiac myocytes. Cell Physiol. Biochem. 20:157-166, 2007.

Meyer, M., Q. Zhang, K. Khurana, P.M. Scholz and H.R. Weiss. Negative functional effects of natriuretic peptides are attenuated in hypertrophic cardiac myocytes by reduced particulate guanylyl cyclase activity. J. Cardiovasc. Pharmacol. 49:100-105, 2007.

Davidov, T., H.R. Weiss, J. Tse and P.M. Scholz. Chronic nitric oxide synthase blockade desensitizes the heart to the negative metabolic effects of nitric oxide. Life Sci. 79:1671-1680, 2006.

Moalem, J., H.R. Weiss, T. Davidov, R. Rodriguez, B. Molino, M.J. Lazar and P.M. Scholz. Heart failure reduces both the effects and interaction between cyclic GMP and cyclic AMP. J. Surg. Res. 134:300-306, 2006.

Su, J., J. Tse, P.M. Scholz and H.R. Weiss. Altherations in ventricular myocyte contraction caused by C-type natriuretic peptide and nitric oxide in eNOS-/- mice. J. Molec. Cell. Cardiol. 39:920-928, 2005.

Chi, O.Z., C. Hunter, X. Liu and H.R. Weiss. Effects of VEGF and nitric oxide synthase inhibition on blood-brain barrier disruption in the ischemic and non-ischemic cerebral cortex. Neurol. Res. 27:864-868, 2005.

Zhang, Q., M. Lazar, B. Molino, R. Rodriguez, T. Davidov, J. Su, J. Tse, H.R. Weiss and P.M. Scholz. Reduction in interaction between cyclic GMP and cyclic AMP in dog ventricular myocytes with hypertrophic failure. Am. J. Physiol. 289:H1251-H1257, 2005.

Zhang, Q., P. M. Scholz, Y. He, J. Tse and H.R. Weiss. Cyclic GMP signaling and regulation of SERCA activity during cardiac myocyte contraction. Cell Calc. 37:259-266, 2005.

Staff:

Xia Liu, M.D., Instructor

Tao Tan , Graduate Student

Jason Luciano , Medical Student

Graduate Program Membership:

Physiology and Integrative Biology

Neuroscience

Biomedical Engineering