So calcium flows in through these channels, and to prevent calcium levels from getting too high, cells kick excess calcium right back out with ATP-dependent calcium pumps as well as sodium calcium exchangers.

所以，钙离子通过这些通道流入细胞内，但为防止细胞内的钙离子浓度过高，细胞使用依赖于ATP的钙离子泵、钠钙交换通道将多余的钙离子排出细胞。