@DavidPS Thanks for your reply. Yes I'm aware of the iNOS bashing but reckon it's partly a chicken-and-egg problem – i.e. is removing the substrates to NO solving the underlying inflammatory issues or merely hiding them? Is keeping furniture in your house the actual fire hazard or is that only an issue because there are smoldering floorboards?
In any case I think Cit/Arg are daft ways for wanting to reduce hypertension, akin to trying to lower blood pressure by riding a continuous niacin-flush wave.
In the long run, however, Cit helps to maintain eNOS functionality. Which is universally accepted as beneficial? I deem Cit to be greatly preferred over Arg because of its greater systemic distribution beyond the tissues of initial exposure (GI lymphatics, liver).
And I see Cit in the context of glycine because Cit's ultimately a substrate for proline, complementing Gly's impact on systemic vasculature and collagen structures, which then leads back to the contexts in this thread.
I don't have an answer to the Arg/Lys and shingles/viral phenomena. I strongly suspect it's also a workaround to suppress immunological or excitatory pathways which ought to be cleared up from another angle.
One thought towards this is that since Arg is a precursor to Pro perhaps these peeps could also benefit from more Gly availability – because a greater ratio of Pro (or of ascorbic acid for that matter, or especially both in combination) may use Gly for collagen synthesis and in doing so rob other cells and tissues of what little amount of Gly had been available to them for their respective functions. In some circumstances elevated (OH)Pro deposits seem to be a culprit and are alleviated by more Gly, like in liver fibrosis by chronic alcoholism in rodents (link, link). In people with metabolic syndromes, plasma Gly's also been found to be depressed and it raises upon introducing physical improvements but, reciprocally, supplementing Gly by itself helps to bring about physical improvements of various aspects of metabolic syndrome (link, link).
