The Total Urine Nitrates (NOx) Test

Nitric Oxide is one of the primary vasodilators in the body.  Nitric Oxide is important for blood pressure regulation and overall cardiovascular health. Nitric Oxide also contributes to healthy perfusion of the genitourinary system.

The Meridian Valley Lab Total Urine Nitrates test provides a clinically important tool in the evaluation and management of erectile dysfunction (ED).

Erectile Dysfunction & Nitric Oxide

Low nitric oxide synthase (NOS) activity can be a major contributor to erectile dysfunction (ED).  A double-blind, placebo controlled study assembled 50 men aged 50 to 75 years who were then treated with L-arginine for their ED.  These men had confirmed ED of at least 6 months duration.

The researchers found that the men who responded well to L-arginine “had lower urinary NOx [nitrate and nitrite] levels before therapy and showed greatly increased plasma and urinary NOx after treatment.” In other words, low total urine nitrate levels at baseline predicted a favorable response to L-arginine therapy and an improvement in the ED symptoms.

Androgens and Nitric Oxide Pathway Activity

Androgens such as testosterone and DHEA are well known contributors to libido and erectile function.  Androgens also play a pivotal role in nitric oxide synthase activity, as adequate testosterone is required to regulate NOS in the corpus cavernosum.

The Meridian Valley Lab 24-hr urine ComprehensivePlus hormone panel provides a means to simultaneously assess androgens and nitric oxide status.  This simultaneous measurement empowers clinicians and patients with one of the most detailed methods available for evaluating the root cause of erectile dysfunction.

Female Patients

Healthy nitric oxide pathway activity confers cardiovascular benefit in both genders.  Nitric oxide levels are typically higher in premenopausal women, and may partially contribute to the lower incidence of cardiovascular disease observed in this population.  In contrast, menopausal women have reduced nitric oxide synthesis, possibly contributing to the rise in cardiovascular events experienced in the female aging process.

Nitric oxide plays a role in bone health via its function as an intermediary in estrogen signaling. Urine nitric oxide metabolites may also be a helpful predictor of preeclampsia in pregnant women if tested early in the 3rd trimester.

Metabolic Syndrome and Low Urine Nitrates

It is well known that insulin resistance and type II diabetes predispose patients to poor circulation and peripheral perfusion.  Nitric oxide production is decreased in insulin resistant patients and may contribute to this Phenonmenon .

In Conclusion

Nitric oxide is an important agent in cardiovascular, peripheral vascular and erectile health.  Urine nitrate levels are a good reflection of endogenous nitric oxide synthesis, and are a useful tool in assessing the underlying cause of ED.  The Total Urine Nitrates test predicts which patients are the best candidates for nitric oxide pathway promoters in the treatment of ED.

The Meridian Valley Total Urine Nitrates test can be ordered individually and is a part of the 24hr urine ComprehensivePlus panel.


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