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 channel opener Calcium channel opener A calcium channel opener is a type of drug which facilitates ion transmission through calcium channels. An example is Bay K8644, which is an analogue of nifedipine that specifically and directly activates L-type voltage-dependent calcium channels. In contrast to Bay K8644, which is not for clinical use, Ambroxol is a frequently used mucolytic drug that triggers lysosomal secretion by mobilizing calcium from acidic calcium stores. This effect does most likely not occur by a direct interaction between the drug and a lysosomal calcium channel, but indirectly by neutralizing the acidic pH within lysosomes. Calcium permeable ion channels