Intestinal Transport of Calcium and Phosphate in Experimental Magnesium Deficiency.

Publisher Website
Google Scholar
Abstract
The concentrative transport of Ca by everted intestinal loops in vitro and the permeability of the small intestinal wall to this ion were determined in intestinal preparations from vitamin D deficient and vitamin D treated Mg deficient and control rats. Concentrative transport of Ca by rat small intestine in vitro is altered by the presence or absence of Mg in the medium but not by Mg depletion of the animals. The permeability to Ca of the intestinal preparations was not influenced by Mg deficiency. The effects of Mg depletion of the rat and of the presence of Mg in the medium on concentrative transport of inorganic PO4 by the small intestine in vitro were studied. Concentrative transport of PO4 by intestinal loops incubated in Mg++ containing buffer was less than by those incubated in Mg++ free buffer. Intestinal loop preparations from Mg deficient animals transferred PO4 to a greater extent than those obtained from control rats; this difference was observed both in the presence and absence of Mg++ in the buffer solution. Mg deficiency also reduced the concentration of serum P and increased the excretion of PO4 in the urine. Mg influences the PO4 transport systems which control phosphate concentrations in extracellular fluids.