New Methods to Evaluate Endothelial Function: Evaluation of Endothelial Function by Hemoglobin-Nitric Oxide Complex Using Electron Paramagnetic Resonance Spectroscopy

Abstract

Abstract. This minireview describes the practical use of assay systems to detect nitric oxide (NO) by electron paramagnetic resonance (EPR) spectroscopy for evaluation of endothelial functions. The iron(II)-dithiocarbamate complexes, such as iron(II)-(N-methyl-D-glucamine dithiocarbamate), are commonly used in EPR detection of NO both in vivo and in vitro. However, due to their redox activity, these complexes have some drawbacks that limit their usefulness for the detection of NO. On the other hand, the measurement of hemoglobin-NO adduct (HbNO) in whole blood by the EPR method seems relevant for the assessment of systemic NO levels. However, ceruloplasmin and an unknown radical species overlapping the same magnetic field as that of HbNO, which makes it physically impossible to measure small amounts of HbNO. Thus, to reveal the EPR spectrum of HbNO, we developed the EPR signal subtraction method, which is based on the computer-assisted subtraction of the digitized EPR spectrum of HbNO-depleted blood from that of the sample blood using software. Using this technique, we succeeded in measuring the steady blood HbNO level as an index of NO by the EPR HbNO signal subtraction method. We also demonstrated that temocapril reduces abnormalities of NO dynamics in the L-NAME (N w -nitro-L-arginine-methylester)-induced endothelial dysfunction of rats using the EPR HbNO signal subtraction method.

Endovascular stent-induced alterations in host artery mechanical environments and their roles in stent restenosis and late thrombosis

“…In contrast, disturbed flow with LSS is prothrombotic and promigration, which can lead to the genesis/development of AS ( Fig. 4c ) [ 67 ].…”

A new method for the assessment of endothelial function with peripheral arterial volume

“…The measurement of pulsatile volume changes of index finger during reactive hyperemia has been proved to be an effective way to evaluate endothelial function [ 10 ]. Forearm plethysmography was also shown to be a useful method to assess endothelial function [ 11 , 12 ]. So we used a novel oximeter-like finger probe (peripheral arterial volume [PAV]) to measure the changes of pulsatile blood flow volume during reactive hyperemia in our study, detecting the changes of hemoglobin (Hb) flow.…”