Changes in intestinal calcium transport and binding in magnesium-deficient chicks.

Disruption of membrane integrity and function has been reported previously as one of the predominant effects of magnesium deficiency. In the current study, we have examined the uptake and binding of calcium by intestinal brush border membrane vesicles from chicks and investigated the effects of Mg deficiency on these processes. Both uptake and binding of calcium were significantly decreased in the membrane vesicles from animals given the magnesium-deficient diet. In addition, the calcium-binding activity of proteins isolated by chromatography on DE-52 cellulose of mucosal extracts was altered by the magnesium deficiency.