Possible Interaction: Norepinephrine and Ascorbate

“Ascorbic acid ascorbate ) participates in critical steps of the biosynthesis of norepinephrine , including those mediated by tyrosine hydroxylase (TH) and dopamine-β-hydroxylase (DBH).”

“However, treatment of cells with ascorbate for 6 h or more markedly increased norepinephrine synthesis, such that intracellular ascorbate and norepinephrine increased in parallel with half maximal intracellular concentrations of about 1 mM ascorbate and 150 μM norepinephrine.”

“ Ascorbate significantly enhances … nM NE contractions by at least twofold at all ascorbate concentrations >15 microM, including the entire physiological range of 40-100 microM. Ascorbate preloading … washout followed by NE exposure produces significantly greater contractions than NE without ascorbate preloading but significantly lower than NE simultaneously with ascorbate.”

“The omission of ascorbate from the external medium drastically reduced the norepinephrine production without affecting the net rate of dopamine uptake.”

“It seems probable that ascorbate may enhance the activity of endogenous norepinephrine in the MBH and, thereby, lead to increased release of LHRH.”

“While ascorbate amplification improves detectability of dopamine and norepinephrine , it also introduces ambiguity since changing catechol concentrations cannot be distinguished from changing ascorbate concentrations.”

“The epinephrine and norepinephrine contents of chromaffin cell cultures supplemented with ascorbate for 7 days were increased approximately 10% compared to cultures without added ascorbic acid; ascorbate had no effect on chromaffin cell opioid peptide levels.”

“The addition of ascorbate to the culture medium increases the storage of norepinephrine in both steroid‐treated and untreated cells.”

“ Ascorbate is an antioxidant and its role is to prevent the decomposition of tracer quantities of added 'Hor '4C-labelled biogenic amines (e.g. dopamine, norepinephrine , DOPA, serotonin).”

“Measurements of O2 uptake with a platinum electrode and spectrophotometric determinations of TPNH oxidation showed that ascorbate increased the rates of O2 uptake and TPNH oxidation, while noradrenaline retarded these reactions.”