NA/NE(Noradrenaline/Norepinephrine) ELISA Kit (E-EL-0047)

This ELISA kit uses the Competitive-ELISA principle. The micro ELISA plate provided in this kit has been pre-coated with Universal NA/NE. During the reaction, Universal NA/NE in the sample or standard competes with a fixed amount of Universal NA/NE on the solid phase supporter for sites on the Biotinylated Detection Ab specific to Universal NA/NE. Excess conjugate and unbound sample or standard are washed away, and Avidin-Horseradish Peroxidase (HRP) conjugate are added to each micro plate well and incubated. Then a TMB substrate solution is added to each well. The enzyme-substrate reaction is terminated by the addition of stop solution and the color turns from blue to yellow. The optical density (OD) is measured spectrophotometrically at a wavelength of 450 nm ± 2 nm. The concentration of Universal NA/NE in tested samples can be calculated by comparing the OD of the samples to the standard curve.

Norepinephrine (noradrenaline, NE/NA) functions as both a neurotransmitter and a hormone and is formed from dopamine by dopamine beta-hydroxylase. It is the N-demethylated counterpart of epinephrine within the catecholamine family and is produced mainly by sympathetic postganglionic neurons and by central noradrenergic nerve terminals, with a smaller amount released by the adrenal medulla into the circulation. It is stored in synaptic vesicles and discharged upon nerve firing, and its signal is terminated by reuptake and by enzymatic degradation. As the principal sympathetic neurotransmitter it mediates the fight-or-flight response through alpha- and beta-adrenergic receptors, regulating vascular tone, blood pressure, heart rate and cardiac contractility. Centrally, noradrenergic projections arising from the locus coeruleus regulate arousal, vigilance, attention, mood and cognitive alertness, and they modulate sensory processing and memory. Measurement of norepinephrine in plasma, urine or cerebrospinal fluid is used to assess sympathetic activity, autonomic function and stress responses. Elevated levels occur in pheochromocytoma and hypertension, whereas reduced levels indicate peripheral neuropathy. The metabolites normetanephrine and vanillylmandelic acid are often measured alongside the parent amine. Because the catecholamine is unstable and highly sensitive to posture and stress, standardized collection is required for reliable determination.