T Nation

Cell Transport Protein, Magnesium


the magnesium ion i taken into the cell via the magnesium/ATPase pathway, if we wnted to get magesium into the cell though another route, if we bound magnsium to something like an amino acid, would it be possible for the magnesium+amino acid to get into the cell via the amino acid pathway?


I don't think so because the amino acid chelate, while helping absorption in the gut, will be cleaved. 55% of plasma magnesium is unbound, 32% bound to protein, and 13% complexed with citrate, phosphorus, and other ions.


so you're saying it get into the gut wall via the amino acid pathway? but once in the gut cell it will be broken? so what if this magnesium+amino acid chelate was intravenously infused then it would be able get into the cell through the amino acid pathway?


I don't know. I looked but didn't find any research pertaining to that particular question. Some magnesium supplements are marketed based on ability to target tissues selectively based on the chelate used (these are claims, I have not seen facts either proving or disproving). The body is quite good at taking up magnesium from the blood and maintains plasma levels by breaking down bone as well as increasing re-absorption in the kidneys and absorptive mechanisms in the gut.


@peter orban, you do believe a stable magnesium+amino acid chelate can enter the gut cell through the amino acid pathway? beside the regular route the magnesium/ATPase pathway


I don't know, most magnesium is absorbed by diffusion across the Brush Border Membrane. It seems that in studies at doses above the carrier mediated saturable intake (there are two ways, carrier and diffusion) amino acid magnesium chelates absorb better than magnesium oxide, but not significantly better than food source and slightly less well than magnesium citrate.

If I was pressed to guess, I would say in most instances, the absorption is by diffusion as the carrier mediated pathway is easily saturated.

As for your earlier intravenous question, this would be inadvisable as the magnesium levels in blood are very closely regulated and disruptions may lead to death, although intravenous loading is a (very invasive) way to test deficiency I don't suggest it as a way to get more magnesium.

Supplementing with magnesium citrate works quite well and is safe for all those who have working kidneys.