Calcium Absorption || calcium absorption and vitamin d || calcium absorption and magnesium || what increase calcium absorption
Calcium absorption site Calcium is actively absorbed from the duodenum and proximal jejunum against electrochemical gradients with the help of a Ca 2+ ATPase and at least, a calcium-binding protein (CBP) of intestinal mucosal cells. Transcellular route: Transcellular movements involves three sequential steps - from the intestinal lumen to the intestinal mucosal cell across the brush border within the cell from the lumen to the serosal site (between the blood vessels and intestinal mucosal cell) finally extrusion from the cell into the blood circulation These three steps are regulated by calcitriol, the biologically active form of vitamin D. Paracellular route: It involves passive calcium transport through the tight junction between the mucosal cells. The salient features of paracellular transport include - It is dependent on the nutritional and physiological regulation It is concentration-de...