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Associate Professor
Ph.D.: University of Missouri-Columbia
Postdoctoral: New York Medical College

Carbon monoxide is formed as an end-product of the biological degradation of heme. This reaction is catalyzed by a virtually ubiquitous enzyme, heme oxygenase. While once regarded solely as a stable metabolic waste product, it is now clear that endogenously-formed carbon monoxide plays an important role in cardiovascular regulation. Accordingly, my group is devoted to determine the roles of endogenously-formed carbon monoxide in the regulation of blood pressure.

systemic hemodynamics an renal function. The heme-heme oxygenase-carbon monoxide system can be activated by providing heme substrate, or inhibited using non metabolizable heme analogs such as Zn-deuteroporphyrin 2,4-bis glycol or Cr mesoporphyrin. As blood pressure is a product of cardiac output, vascular resistance and renal function, we examine the biological actions of the heme-heme oxygenase-carbon monoxide system in both intact animals and in isolated organ preparations. Towards this end we employ a wide array of cardiovascular experimental preparations.

The systemic hemodynamic status can be evaluated in awake rats. Specifically an aortic flow probe placed around the ascending aorta can serve to measure cardiac output, while chronically implanted arterial catheters are used to measure the arterial pressure. The local actions of the endogenous-carbon monoxide system are elucidated through the use of isolated superfused vessels and Langendorff-heart preparations.

Our studies focus on the chronic and acute renal and hemodynamic effects of altered endogenous production of carbon monoxide using normotensive and hypertensive rat models. Such studies provide valuable information about the physiological roles of carbon monoxide as they relate to cardiovascular health.

For more information regarding our laboratory and experimental activities, please visit our independently maintained laboratory website at http://members.cox.net/robertj393/welcome

Recent Publications:

A PubMed listing of research publications for Robert A. Johnson, Ph.D.

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