Plasma nitrite/nitrate level is inversely correlated with plasma low‐density lipoprotein cholesterol level

Abstract

SummaryBackground: Plasma nitritehitrate (NOx) is a stable end product of the vasodilator nitric oxide (NO). However, there are few reports about plasma NOx levels in humans.Hypotlzrsis: The purpose of this study was to assess the availability of plasma NOx for evaluating basal endogenously-synthesized or endothelium-derived NO, and to examine whether NOx levels are lowered in patients with coronary artery disease (CAD) or its risk factors.Metlzods: Plasma NOx levels were measured using an automated system based on the Griess reaction. NOx levels for a 24-h period reproducibly became lowest at 6 A.M. in restricted healthy volunteers, and became stable in inpatient volunteers at 6 A.M. within 4 days after admission.Remlts: Based on these findings, NOx levels at 6 A.M. in inpatients can be considered as the basal levels. In 40 inpatients suspected of CAD (28 men, 12 women; mean age 60 f 1 1 years), the basal levels of NOx were not related to CAD and its risk factors, except for hypercholesteroleniia. The NOx level of patients with hypercholesterolemia was significantly lower than that ofpatients with normal cholesterol (n = 16,34 16 pmol/l vs. n = 24,49 k 23 pmoVI, p < 0.03). Furthermore, the NOx levels coirelated negatively with the total cholesterol and low-density lipoprotein cholesterol levels (r = -0.40, p < 0.01 ; r = -0.37, p < 0.003, respectively), but not with other lipid fraction levels.

Measurement of nitric oxide, nitrite and nitrate using a chemiluminescence assay:an update for the year 2000

“…They also found temporal variability in NOx levels, which were most reproducible and lowest at 0600 [64]. This confirmed the work of Nakashima, who found that treatment of hypercholesterolemic adults with the cholesterol lowering agent, Simvastatin, increases plasma NOx (from 8 ± 17 µmol/l to 57 ± 32 µmol/l), within 12 weeks, in a manner that correlated with the rise in high density lipoprotein [65].…”

“…Tanaka et al reported normal plasma NOx values of 4.9±2.3 × 10 -5 M (49 µmol/l) [64] and also noted that NOx levels were lower for patients with hypercholesterolemia. They also found temporal variability in NOx levels, which were most reproducible and lowest at 0600 [64].…”

Long-Term Treatment With Imidapril but Not With Nifedipine Enhances Plasma NOx Concentration in Patients With Essential Hypertension

“…Besides the present study, we also previously demonstrated that long-term treatment with simvastatin, a HMG-CoA reductase inhibitor, significantly enhances plasma NOx concentration in patients with hypercholesterolemia (16) and that plasma NOx level is inversely correlated with plasma level of lowdensity lipoprotein cholesterol in humans (24). However, whether NOx is a reliable marker of NO formation in vivo is still controversial, and indeed there are conflicting facts regarding plasma NOx level in hypertensive individuals: two studies reported that plasma NOx concentrations were significantly reduced in patients with essential hypertension compared to those in normotensive healthy subjects (12,25) whereas one study showed that plasma NOx levels were similar in refractory hypertensive patients and normotensive healthy subjects (26).…”

Antihypertensive Potential and Mechanism of Action of Astaxanthin: III. Antioxidant and Histopathological Effects in Spontaneously Hypertensive Rats

“…Some reports have noted that there was an increased NOx level in coronary artery disease (CAD) in patients with abnormal lipid profiles, 25) while another study reported that the NOx level was not related to the disease and the level decreased only in hypercholesteremic patients with CAD. 26) The inhibitory effects of ASX against lipid peroxidation and lipoprotein oxidation have been mentioned in a number of studies. 27,28) In this experiment, the effect of ASX-O on lipid peroxidation was not significant compared to the olive oil control, which also showed a similar effect.…”