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Graduate Student-Faculty Seminars
Wednesday, November 2,
Cullimore Hall Room 611
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The Effect of Interactions Between Nitric Oxide and Oxygen on Tissue Oxygenation
Yogesh Joshi
Department
of Mathematical Sciences
New
Jersey Institute of Technology
Abstract
Nitric oxide (NO) is a highly diffusible gas that is
synthesized from the amino acid L-arginine by a
family of enzymes termed NO syntheses (NOS). The physiological role of NO in
the maintenance of vascular tone and in cellular defense is well-established. Apart from its important role in vasodilation, NO is closely linked to O_2 transport to
tissue and oxygen consumption by tissue, because all NOS isoforms
(eNOS, nNOS and iNOS)
require O_2 to produce NO and tissue O_2 consumption is reversibly inhibited by
NO. In addition, the rate of consumption
of NO by cells (e.g, hepatocytes)
depends linearly on both the NO and O_2 concentrations. To investigate the
above interactions, mathematical models have been developed for the coupled
mass transport of NO and O_2 between microvessels and
tissue. We will discuss a simple 1-D
model of coupled NO-O_2 transport, as well as a radially
symmetric model for the transport in and around an arteriole that includes
several different layers - representing red cells and plasma, endothelium,
vascular wall and tissue. Both models show that NO can increase O_2 delivery to
more distal regions by inhibiting O_2 consumption near microvessels