Laboratory Medicine Program

Nitric oxide
(NO)

Clinical Decription:
Nitric oxide (NO) is a major secretory product that initiates host defense,homeostatic and development functions by either direct effect or intracellular signaling. Nitric oxide is the product of a five-electron oxidation of the amino acid L-arginine mediated by one of three isoforms of nitric oxide synthase. As a direct efector, NO is thought to activate regulatory proteins, kinases, and proteases that are directed by reactive oxygen intermediates. As an messenger molecule, NO covalently interacts with target molecules based on redox potential. Activation of the immune system is associated with an increase in macrophage NO production. NO exerts a variety o homeostatic influences as an activator of soluble guanylyl cyclase, a neuronal potentiator, a peripheral nervous system transmitter and a contraction regulator of both smooth muscle and vascular tissue. In addition, NO has been linked to the formation of olfactory and synaptic memories and remolding. This assay involves the conversion of nitrate to nitrite by the enzyme nitrate reductase. The detection of total nitrite is then determined as a coloured azo-dye product of the Griess Reaction that absorbes visible light at 540 nm.
<br/><em>R&D Systems Total Nitric Oxide Assay package insert.</em>

Method: Colorimetric; Colourimetric microplate

Component Tests Used: n/a

Reference Ranges Used:
N/A

Specimen Type: Lavender EDTA
Collected In: EDTA
Volume: 5 mL (minimum: 1 mL)

Shipping: room temperature or 4C

Special Instructions: Centrifuge and aliquot sample.

Testing Schedule(s): on request, but must be a minimum of 25 samples, 4 week prior arrangement.

Turnaround Time: 20 days

For more information, call 416.340.5227 or 1.866.865.5227