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Carbon monoxide--a regulator of vascular tone in hypoxia?
Zygmunt Chodorowski1, Jacek Sein Anand, Livia Nowak-Banasik
11st Clinic of Intemal Diseases and Acute Poisonings, Medical University of Gdańsk.
Abstract:
Carbon monoxide is a side product of enzymatic degradation of heme--a reaction catalyzed by heme oxygenase (HO). There are three independent molecular forms (isozymes) of heme oxygenase in man. Isoforms HO-2 and HO-3 are constitutive. More detailed studied isoform HO-2 is especially abundant in the human brain. In contrast to isoforms: HO-2 and HO-3, isoform HO-1 is an inducible species of heme oxygenase. Seen in other tissues, expression of HO-1 is also manifested in the endothelium and smooth muscle of blood vessels. Accumulated experimental data indicate more and more clearly on the possible role of endogenous carbon monoxide in cell cytoprotection, and shows it as a probable factor participating in modulation of the vascular tonus in hypoxia.
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