Calcium pump Calcium pump Calcium pumps are a family of ion transporters found in the cell membrane of all animal cells. They are responsible for the active transport of calcium out of the cell for the maintenance of the steep Ca electrochemical gradient across the cell membrane. Calcium pumps play a crucial role in proper cell signalling by keeping the intracellular calcium concentration roughly 10,000 times lower than the extracellular concentration. Failure to do so is one cause of muscle cramps. The plasma membrane Ca ATPase and the sodium-calcium exchanger are together the main regulators of intracellular Ca concentrations. Ca has many
Calcium supplement Calcium supplement Calcium supplements are salts of calcium used in a number of conditions. Supplementation is generally only required when there is not enough calcium in the diet. By mouth they are used to treat and prevent low blood calcium, osteoporosis, and rickets. By injection into a vein they are used for low blood calcium that is resulting in muscle spasms and for high blood potassium or magnesium toxicity. Common side effects include constipation and nausea. When taken by mouth high blood calcium is uncommon. Calcium supplements, unlike calcium from dietary sources, appear to increase the risk of kidney stones.